Corrections log
Historical borders are hard to get right, and we would rather fix a mistake in public than leave it on the map. This page lists every correction made to the atlas.
How to report an error
- On the map, go to the year and place that looks wrong and press the flag button (Report an error) at the top. It opens an email to us with the year, map mode, position and a link to that exact view already filled in.
- Or write to [email protected] with the year, the place and what you think is wrong.
- A source helps a great deal: a published historical atlas, a scholarly book or article, or a primary document.
What happens next
We check each report against published sources. If the map is wrong, we fix it in the next update and add a line below. If you tell us a name or handle to use, we credit you by it; otherwise the fix is listed without a name. We never publish your email address.
Corrections since launch
| Date fixed | Year(s) on the map | Map mode | What changed | Source | Thanks to |
|---|---|---|---|---|---|
| None yet. The first fix after launch will appear here. | |||||
Corrections made before launch (2026)
Every era map was checked and corrected while the atlas was built: 331 corrections across 57 maps. These are the same notes the map shows under Corrections in this map for each year. Open a year to see its list.
10,000 BCE · Neolithic (1)
- Named the remaining unclaimed regions after their regional peoples.
8,000 BCE · Neolithic (1)
- Named the remaining unclaimed regions after their regional peoples.
5,000 BCE · Neolithic (1)
- Named the remaining unclaimed regions after their regional peoples.
4,000 BCE · Neolithic (1)
- Named the remaining unclaimed regions after their regional peoples.
3,000 BCE · Bronze Age (6)
- Mesopotamia c. 3000 BCE was a patchwork of Sumerian city-states (Uruk, Ur, Kish), not a kingdom of Ur.
- The Hurrian kingdoms date from after 2300 BCE.
- The mature Indus cities date from c. 2600 BCE.
- The Bantu expansion began c. 1500 BCE; in 3000 BCE Bantu speakers lived around the Nigeria–Cameroon border.
- Filled the rest of the world with the hunter-gatherer and farming peoples of the 2000 BCE map.
- Named the remaining unclaimed regions after their regional peoples.
2,000 BCE · Bronze Age (6)
- The source map spreads Tai and Austroasiatic rice farmers over most of China and India; replaced with the regional cultures of c. 2000 BCE.
- The Ur III state fell c. 2004 BCE; the map shows its last years.
- The Bantu expansion had barely begun c. 2000 BCE.
- Sub-Saharan Africa filled with the farming and foraging peoples of the 1500 BCE map.
- Added Minoan Crete (Old Palace period).
- Named the remaining unclaimed regions after their regional peoples.
1,500 BCE · Bronze Age (10)
- The Shang ruled the Yellow River c. 1500 BCE; the Zhou came in 1046 BCE.
- The source map repeats 1000 BCE here; the Levant c. 1500 BCE was Canaanite city-states under Egyptian rule.
- Northern Mesopotamia was the Hurrian kingdom of Mitanni; Assyria was its vassal.
- Urartu appears only c. 860 BCE.
- The Aramaeans appear after 1100 BCE.
- The Phrygians arrived after 1200 BCE; western Anatolia was Arzawa.
- The kingdom of Saba dates from c. 1000 BCE.
- The Urnfield culture begins c. 1300 BCE.
- Filled unclaimed land with peoples and cultures from neighbouring maps.
- Named the remaining unclaimed regions after their regional peoples.
1,000 BCE · Iron Age (2)
- Urartu appears only c. 860 BCE.
- Named the remaining unclaimed regions after their regional peoples.
700 BCE · Iron Age (5)
- The Neo-Assyrian Empire ruled Mesopotamia, Syria and the Levant c. 700 BCE.
- Israel fell to Assyria in 722 BCE; Judah was an Assyrian vassal.
- Egypt was ruled by the Kushite 25th Dynasty.
- Filled unclaimed land with peoples and cultures from neighbouring maps.
- Named the remaining unclaimed regions after their regional peoples.
500 BCE · Classical Antiquity (3)
- Northern India was divided among the Mahajanapadas.
- Filled unclaimed land with peoples and cultures from neighbouring maps.
- Named the remaining unclaimed regions after their regional peoples.
400 BCE · Classical Antiquity (3)
- The Xiongnu confederation formed c. 209 BCE.
- Filled unclaimed land with peoples and cultures from neighbouring maps.
- Named the remaining unclaimed regions after their regional peoples.
323 BCE · Classical Antiquity (3)
- Filled gaps in the source map from the nearest map (within 50 years).
- Filled unclaimed land with peoples and cultures from neighbouring maps.
- Named the remaining unclaimed regions after their regional peoples.
300 BCE · Classical Antiquity (3)
- Filled gaps in the source map from the nearest map (within 50 years).
- Filled unclaimed land with peoples and cultures from neighbouring maps.
- Named the remaining unclaimed regions after their regional peoples.
200 BCE · Classical Antiquity (3)
- Bactria and the Bosporan Kingdom were independent Hellenistic states.
- Filled unclaimed land with peoples and cultures from neighbouring maps.
- Named the remaining unclaimed regions after their regional peoples.
100 BCE · Classical Antiquity (4)
- The Mauryan Empire fell in 185 BCE.
- The Kushan Empire was founded c. 30 CE; Bactria was held by the Yuezhi.
- Filled unclaimed land with peoples and cultures from neighbouring maps.
- Named the remaining unclaimed regions after their regional peoples.
1 BCE · Classical Antiquity (2)
- Filled unclaimed land with peoples and cultures from neighbouring maps.
- Named the remaining unclaimed regions after their regional peoples.
100 · Classical Antiquity (2)
- Filled unclaimed land with peoples and cultures from neighbouring maps.
- Named the remaining unclaimed regions after their regional peoples.
200 · Classical Antiquity (3)
- The Kushan Empire still held Bactria and Gandhara.
- Filled unclaimed land with peoples and cultures from neighbouring maps.
- Named the remaining unclaimed regions after their regional peoples.
300 · Classical Antiquity (5)
- The Sasanians replaced the Parthians in 224.
- The Satavahanas ended in the 220s; the Vakatakas ruled the Deccan.
- The Gupta Empire proper begins with Chandragupta I (c. 320).
- Filled unclaimed land with peoples and cultures from neighbouring maps.
- Named the remaining unclaimed regions after their regional peoples.
400 · Classical Antiquity (2)
- Filled unclaimed land with peoples and cultures from neighbouring maps.
- Named the remaining unclaimed regions after their regional peoples.
500 · Early Middle Ages (6)
- South China was ruled by the Southern Qi (479–502), not the Jin.
- The Alchon Huns (Toramana) ruled the Punjab c. 500.
- The Western Roman Empire ended in 476.
- Added the Hephthalite Empire in Bactria and Sogdia.
- Filled unclaimed land with peoples and cultures from neighbouring maps.
- Named the remaining unclaimed regions after their regional peoples.
600 · Early Middle Ages (5)
- Mataram was founded in 732; central Java was the Kalingga kingdom.
- Added the Western Turkic Khaganate.
- Tibet was being united by the Yarlung kings (Tibetan Empire from 618).
- Filled unclaimed land with peoples and cultures from neighbouring maps.
- Named the remaining unclaimed regions after their regional peoples.
700 · Early Middle Ages (9)
- The Tang replaced the Sui in 618.
- The Sasanian Empire fell to the Arabs (636–651).
- Iberia was Visigothic until the Arab conquest of 711.
- The Western Turks collapsed in 657; the Türgesh ruled Zhetysu.
- Goguryeo fell in 668; Balhae was founded in 698.
- Baekje fell in 660 and Korea was unified by Silla.
- The Pala dynasty began c. 750.
- Filled unclaimed land with peoples and cultures from neighbouring maps.
- Named the remaining unclaimed regions after their regional peoples.
800 · Early Middle Ages (3)
- Added the Oghuz Yabgu State, the Kimek Khaganate and the Karluks.
- Filled unclaimed land with peoples and cultures from neighbouring maps.
- Named the remaining unclaimed regions after their regional peoples.
900 · Early Middle Ages (5)
- The Tibetan Empire collapsed in 842; Tibet was divided.
- The Uyghur Khaganate fell in 840; its successors held only Gansu and Turpan.
- The Magyars had conquered the Carpathian Basin (895–900).
- Filled unclaimed land with peoples and cultures from neighbouring maps.
- Named the remaining unclaimed regions after their regional peoples.
1000 · High Middle Ages (6)
- The Western Xia was proclaimed in 1038; the Tanguts already ruled the Ordos.
- Added the Kara-Khanids (who took Bukhara in 999), Qocho and Khotan.
- Greenland: only the Norse settlements (c. 985–1450) are shown, not the whole ice sheet.
- Filled unclaimed land with peoples and cultures from neighbouring maps.
- Named the remaining unclaimed regions after their regional peoples.
- The Khitan homeland was the Liao Empire.
1066 · High Middle Ages (8)
- Built from the 1100 map, adjusted to 1066.
- Anatolia was still Byzantine before Manzikert (1071).
- No crusader states yet; Palestine and Damascus were Fatimid.
- Al-Andalus was divided into taifa kingdoms before the Almoravids crossed (1086).
- The Almoravids held only southern Morocco and the Sahara.
- Most of Sicily was still Muslim; the Norman conquest ran 1061–1091.
- Filled unclaimed land with peoples and cultures from neighbouring maps.
- Named the remaining unclaimed regions after their regional peoples.
1100 · High Middle Ages (12)
- The Pratiharas had fallen; the Gahadavalas held Kannauj from c. 1089.
- Sukhothai was founded in 1238; Lavo ruled central Thailand.
- Added the crusader Kingdom of Jerusalem (1099).
- Added the Principality of Antioch (1098).
- Added the County of Edessa (1098).
- Central Anatolia had fallen to the Seljuk Sultanate of Rum after Manzikert (1071).
- Added the Danishmendid emirate in north-central Anatolia.
- Bulgaria was a Byzantine province from 1018 to 1185.
- The Mongols were still separate tribes (Kerait, Naiman, Tatar) until Temüjin.
- Filled gaps in the source map from the nearest map (within 50 years).
- Filled unclaimed land with peoples and cultures from neighbouring maps.
- Named the remaining unclaimed regions after their regional peoples.
1200 · High Middle Ages (14)
- The Liao fell in 1125; the Jurchen Jin ruled north China.
- Iraq was ruled by the revived Abbasid Caliphate.
- The Buyids ended in 1062; Iran was contested by the Khwarazmians.
- The Fatimids ended in 1171; Egypt and Syria were Ayyubid.
- The Ghaznavids fell in 1186 to the Ghurids.
- Delhi was held by Ghurid generals until the Sultanate formed in 1206.
- The Mongol Empire was proclaimed in 1206; in 1200 Temüjin was uniting the tribes.
- Ifat replaced the Sultanate of Shewa only in 1285.
- The Buyids ended in 1062.
- Northern India: Ghurid conquests to Bihar; the Deccan was divided among the Yadavas, Kakatiyas and Hoysalas.
- Filled unclaimed land with peoples and cultures from neighbouring maps.
- Named the remaining unclaimed regions after their regional peoples.
- Corrected (AP review): Castile and Aragon held Toledo, Madrid, Cuenca and Zaragoza; the Almohad frontier ran south of the Tagus.
- Corrected (AP review): central Anatolia was the Seljuk Sultanate of Rum; the crusader states (Jerusalem from Acre, Tripoli, Antioch), Armenian Cilicia and Zagwe Ethiopia are now drawn.
1210 · High Middle Ages (5)
- Built from the 1200 map, adjusted to 1210.
- Philip II took Normandy (1204) and Anjou, Maine and Touraine (1204-05) from King John.
- The Trencavel lands passed to Simon de Montfort after the crusaders took Béziers and Carcassonne in 1209.
- Montpellier passed to Peter II of Aragon by marriage in 1204; Forcalquier joined Provence in 1209.
- Outside Western Europe this map still repeats 1200: the Latin Empire (1204), the Mongol Empire (1206) and the Delhi Sultanate (1206) are not yet drawn.
1279 · High Middle Ages (6)
- Java was ruled by Singhasari (1222–1292).
- Kublai Khan ruled as emperor of the Yuan dynasty (1271).
- The Golden Horde, Chagatai Khanate and Ilkhanate acted as independent states; Rus princes paid tribute to the Golden Horde.
- The Deccan was ruled by the Yadavas, Kakatiyas and Hoysalas; Delhi did not yet hold Gujarat, Malwa or Rajasthan.
- Filled unclaimed land with peoples and cultures from neighbouring maps.
- Named the remaining unclaimed regions after their regional peoples.
1300 · Late Middle Ages (8)
- Majapahit was founded in 1293.
- Pagan fell in 1287.
- Tibet was administered by the Yuan.
- The Russian principalities were tributaries of the Golden Horde.
- The Deccan kingdoms fell to Delhi only in 1307–1323.
- Filled gaps in the source map from the nearest map (within 50 years).
- Filled unclaimed land with peoples and cultures from neighbouring maps.
- Named the remaining unclaimed regions after their regional peoples.
1400 · Late Middle Ages (12)
- China was ruled by the Ming (1368), not the Mongol Great Khanate.
- The Mongols had withdrawn to the steppe as the Northern Yuan.
- The Mongol khanates were independent of each other by 1400.
- Added Muscovy and its neighbours Tver and Ryazan.
- Japan was under the Ashikaga shogunate (1336).
- Srivijaya had been absorbed by Majapahit.
- The Sultanate of Rum ended in 1308; Anatolia was split among beyliks.
- The White and Blue Hordes were the two wings of the Golden Horde, reunited under Tokhtamysh and Edigu.
- After Timur's sack of Delhi (1398) the Sultanate held little beyond Delhi; regional sultanates and Vijayanagara ruled the rest.
- Greenland: only the Norse settlements (c. 985–1450) are shown, not the whole ice sheet.
- Filled unclaimed land with peoples and cultures from neighbouring maps.
- Named the remaining unclaimed regions after their regional peoples.
1450 · Late Middle Ages (4)
- Built from the 1453 map, adjusted to 1450.
- Constantinople is still Byzantine: the Ottomans under Mehmed II took it on 29 May 1453. The Despotate of the Morea was ruled by the emperor's brothers.
- Samarkand, Bukhara and the Ferghana valley were Timurid; Abu Sa'id took Samarkand in 1451.
- Not yet drawn: the English still held Gascony (lost 1451-53) and Calais.
1453 · Late Middle Ages (19)
- Built from the 1492 map, adjusted to 1453.
- Bosnia (1463), Serbia (1459), the Morea (1460) and Trebizond (1461) were not yet Ottoman.
- Skanderbeg's League of Lezhë held northern Albania.
- Karaman and Candar (Isfendiyarids) were independent beyliks.
- Crimea was independent; it became an Ottoman vassal in 1475.
- The Nasrid Emirate of Granada survived until 1492.
- Novgorod (1478), Tver (1485) and other Russian lands were not yet Muscovite.
- Added the Burgundian State of Philip the Good.
- The Teutonic Order still held all of Prussia (until 1466).
- Iran and Iraq were ruled by the Qara Qoyunlu (Black Sheep).
- The Deccan was still the united Bahmani Sultanate.
- Songhai was a small kingdom around Gao; Mali still held the inner Niger.
- The Inca state under Pachacuti covered only the southern Peruvian highlands.
- The Triple Alliance under Moctezuma I held only the Valley of Mexico and its surroundings.
- In 1453 Mongolia was dominated by the Oirats under Esen Taishi.
- The eastern steppe was Abu'l-Khayr's Uzbek Khanate; the Kazakhs split from it c. 1465.
- Filled unclaimed land with peoples and cultures from neighbouring maps.
- Named the remaining unclaimed regions after their regional peoples.
- Corrected (AP review): Samarkand and Bukhara were Timurid, not part of Moghulistan.
1492 · Late Middle Ages (8)
- Added the Inca Empire, missing from the 1492 source map.
- Added the Aztec Triple Alliance as a state.
- Mongolia was the Northern Yuan under Dayan Khan, not the Chagatai Khanate; the Chagatai remnant was Moghulistan.
- The Kazakh Khanate (1465) held the eastern steppe; the Great Horde was the last remnant of the Golden Horde.
- Greenland was unclaimed between the end of the Norse settlements and Danish recolonisation (1721).
- Filled gaps in the source map from the nearest map (within 50 years).
- Filled unclaimed land with peoples and cultures from neighbouring maps.
- Named the remaining unclaimed regions after their regional peoples.
1500 · Early Modern Era (5)
- Mongolia was the Northern Yuan under Dayan Khan; the Chagatai remnant was Moghulistan.
- Greenland was unclaimed between the end of the Norse settlements and Danish recolonisation (1721).
- Filled gaps in the source map from the nearest map (within 50 years).
- Filled unclaimed land with peoples and cultures from neighbouring maps.
- Named the remaining unclaimed regions after their regional peoples.
1530 · Early Modern Era (8)
- After Mohács (1526) Hungary was split between Ferdinand of Habsburg and John Zápolya (an Ottoman vassal); the Ottomans annexed central Hungary only in 1541.
- Mongolia was the Northern Yuan; the Tarim Basin was the Yarkent Khanate (1514).
- Split the source map's 'Islamic and Hindu states' into the sultanates of Gujarat, Malwa, Bengal and Sindh and the Gajapati kingdom.
- Greenland was unclaimed between the end of the Norse settlements and Danish recolonisation (1721).
- Tunis (Hafsid) and Tripoli (Knights Hospitaller, 1530) were not Ottoman until 1551–74.
- Filled gaps in the source map from the nearest map (within 50 years).
- Filled unclaimed land with peoples and cultures from neighbouring maps.
- Named the remaining unclaimed regions after their regional peoples.
1600 · Early Modern Era (10)
- The Inca Empire had fallen to Spain (1532–1572).
- Songhai fell to Morocco at Tondibi (1591).
- The Saadi dynasty replaced the Wattasids in 1549.
- Japan was reunified by 1590.
- Royal Hungary (north and west) was Habsburg; Transylvania was an Ottoman vassal principality.
- Added the Portuguese captaincies along the Brazilian coast.
- Split 'central Asian khanates': the Khalkha/Chahar Mongols, the Oirats, the Yarkent Khanate and the Jurchens.
- Akbar had annexed Gujarat (1573), Bengal (1576), Kashmir (1586), Sindh (1591) and Orissa (1592).
- Filled unclaimed land with peoples and cultures from neighbouring maps.
- Named the remaining unclaimed regions after their regional peoples.
1650 · Early Modern Era (10)
- Vijayanagara had broken into Nayaka kingdoms by 1646.
- Royal Hungary (north and west) was Habsburg; Transylvania was an Ottoman vassal principality.
- Dutch Brazil (1630–1654) held Pernambuco and the north-east coast.
- Inner Mongolia had submitted to the Qing (1635); Khalkha and Dzungaria were independent.
- The Southern Ming still resisted the Qing in the south-west.
- Ahmadnagar was annexed by the Mughals in 1636.
- England was a republic (the Commonwealth) 1649–1660.
- Filled gaps in the source map from the nearest map (within 50 years).
- Filled unclaimed land with peoples and cultures from neighbouring maps.
- Named the remaining unclaimed regions after their regional peoples.
1700 · Early Modern Era (6)
- The Qing had conquered the last Ming loyalists by 1683.
- Dutch Brazil ended in 1654.
- The Khalkha Mongols submitted to the Qing in 1691; the west was the Dzungar Khanate.
- Filled gaps in the source map from the nearest map (within 50 years).
- Filled unclaimed land with peoples and cultures from neighbouring maps.
- Named the remaining unclaimed regions after their regional peoples.
1715 · Early Modern Era (4)
- Great Britain was formed in 1707; the United Kingdom only in 1801.
- Filled gaps in the source map from the nearest map (within 50 years).
- Filled unclaimed land with peoples and cultures from neighbouring maps.
- Named the remaining unclaimed regions after their regional peoples.
1750 · Early Modern Era (7)
- Built from the 1715 map, adjusted to 1750.
- Iran: Nader Shah ended the Safavids (1736); after his murder (1747) Ahmad Shah Durrani founded the Durrani Empire in Afghanistan.
- India: the Mughal emperor still reigned in Delhi, but the Marathas held most of the Deccan, Malwa and Gujarat, and the nawabs of Bengal, Awadh and Hyderabad ruled their provinces independently.
- Europe: Prussia took Silesia (1742); Russia gained the eastern Baltic from Sweden (1721); Naples and Sicily formed a Bourbon kingdom (1735); Sardinia passed to Savoy (1720).
- North America: British colonies from Maine to Georgia; French Canada on the St Lawrence and Louisiana on the lower Mississippi. Many interior nations remained independent.
- West Africa: Asante and Dahomey expanded in the age of the Atlantic slave trade.
- Not yet drawn: Qing control of Tibet (from 1720) and the Rajput, Sikh and Rohilla states; the Habsburgs lost northern Serbia to the Ottomans in 1739.
1783 · Early Modern Era (6)
- Britain and its colonies form one realm (Great Britain, before the 1801 union).
- Louisiana was Spanish from 1762 to 1800; Quebec British from 1763.
- Split 'central Asian khanates' into Khiva, Bukhara, Kokand and the Kazakh juzes.
- Sardinia island belonged to the Kingdom of Sardinia (Savoy).
- Filled unclaimed land with peoples and cultures from neighbouring maps.
- Named the remaining unclaimed regions after their regional peoples.
1800 · Age of Revolutions & Empire (7)
- Louisiana was still Spanish-run (secretly ceded to France in October 1800, sold to the US in 1803).
- The Cape and Ceylon had been taken by Britain (1795–96).
- Sardinia island belonged to the Kingdom of Sardinia (Savoy).
- Filled gaps in the source map from the nearest map (within 50 years).
- Filled unclaimed land with peoples and cultures from neighbouring maps.
- Named the remaining unclaimed regions after their regional peoples.
- Egypt was occupied by the French (1798–1801).
1815 · Age of Revolutions & Empire (10)
- Added the United Kingdom of the Netherlands (Congress of Vienna).
- The Punjab was the Sikh Empire of Ranjit Singh, not Maratha.
- Hong Kong became British only in 1841.
- Restored the Dutch East Indies from the 1800 map.
- Florida was Spanish until 1821.
- The Río de la Plata had been self-governing since 1810.
- Split 'Turan' into Khiva, Bukhara, Kokand and the Kazakh juzes.
- Filled gaps in the source map from the nearest map (within 50 years).
- Filled unclaimed land with peoples and cultures from neighbouring maps.
- Named the remaining unclaimed regions after their regional peoples.
1848 · Age of Revolutions & Empire (20)
- Built from the 1815 map, adjusted to 1848.
- The United States after Texas (1845), Oregon (1846) and the Mexican Cession (1848).
- Spanish America was independent: Mexico, Central America and South America.
- Brazil was an independent empire (1822).
- The Dominican Republic broke from Haiti in 1844.
- Belgium independent (1830); Greece independent (1832).
- Serbia was an autonomous principality under Ottoman suzerainty.
- France had conquered Algeria (1830–1847).
- Kraków was annexed by Austria in 1846.
- Muhammad Ali's Egypt had conquered the Sudan (1820–22).
- Russia had taken Georgia, Armenia and Azerbaijan, and the Kazakh steppe.
- The Sikh Empire was annexed only in 1849.
- Sindh (1843), Arakan and Tenasserim (1826) were British.
- The Marathas were defeated in 1818; their lands were British or princely states.
- Britain claimed all of Australia and New Zealand (1840).
- Cape Colony, Natal and the Orange River Sovereignty were British; Boers held the Transvaal.
- Liberia declared independence in 1847.
- Filled gaps in the source map from the nearest map (within 50 years).
- Filled unclaimed land with peoples and cultures from neighbouring maps.
- Named the remaining unclaimed regions after their regional peoples.
1871 · Age of Revolutions & Empire (11)
- Built from the 1878 map, adjusted to 1871.
- Romania, Serbia and Bulgaria were still under Ottoman suzerainty before 1878.
- Bosnia was Ottoman until the Austrian occupation of 1878.
- Kars and Batumi were Ottoman until 1878; Cyprus until 1878.
- Kokand (annexed 1876) and Khiva (protectorate 1873) were still independent.
- Egypt took Harar (1875) and Darfur (1874) later in the decade.
- Fiji became British in 1874.
- The Transvaal was an independent Boer republic until 1877.
- Filled gaps in the source map from the nearest map (within 50 years).
- Filled unclaimed land with peoples and cultures from neighbouring maps.
- Named the remaining unclaimed regions after their regional peoples.
1878 · Age of Revolutions & Empire (6)
- Removed colonies that did not yet exist: the partition of Africa came after the Berlin Conference (1884–85).
- Britain annexed the Transvaal from 1877 to 1881.
- Filled the African interior with the kingdoms and peoples that still ruled it.
- Filled gaps in the source map from the nearest map (within 50 years).
- Filled unclaimed land with peoples and cultures from neighbouring maps.
- Named the remaining unclaimed regions after their regional peoples.
1880 · Age of Revolutions & Empire (6)
- Removed colonies that did not yet exist: the partition of Africa came after the Berlin Conference (1884–85).
- Britain annexed the Transvaal from 1877 to 1881.
- Filled the African interior with the kingdoms and peoples that still ruled it.
- Filled gaps in the source map from the nearest map (within 50 years).
- Filled unclaimed land with peoples and cultures from neighbouring maps.
- Named the remaining unclaimed regions after their regional peoples.
1900 · Age of Revolutions & Empire (8)
- Brazil was an independent republic (1889), not a Portuguese possession.
- Filled colonial Africa from the 1914 map (Libya Ottoman, Congo Free State under Leopold II).
- By 1900 almost all of Africa had been claimed by European powers; colonial borders taken from the 1914 map.
- North-east New Guinea was German; Papua was British (administered by Australia from 1906).
- Filled gaps in the source map from the nearest map (within 50 years).
- Filled unclaimed land with peoples and cultures from neighbouring maps.
- Named the remaining unclaimed regions after their regional peoples.
- Corrected (AP review): Cuba and Puerto Rico were no longer Spanish (1898); Taiwan was Japanese (1895); Hawaii was a US territory (1898); Malaya was under British control.
1914 · World Wars (3)
- North-east New Guinea was German; Papua was Australian.
- Finland, Georgia, Armenia and Azerbaijan were part of the Russian Empire in 1914.
- Corrected (AP review): Morocco was a French protectorate from 1912; Malaya was under British control; Xinjiang was a province of the Republic of China.
1920 · World Wars (1)
- The Russian Empire had become Soviet Russia; the USSR was formed in 1922.
1930 · World Wars (2)
- The source labels the USSR "White Russia".
- Ibn Saud had conquered Hail (1921) and the Hejaz (1925).
1938 · World Wars (1)
- Saudi Arabia was proclaimed in 1932; Iraq became independent the same year.
1945 · Cold War (2)
- India and Pakistan were partitioned only in 1947.
- Corrected (AP review): Xinjiang was a Chinese province under Nationalist control (the Ili rebellion held only the north-west).
1960 · Cold War (2)
- Vietnam was divided at the 17th parallel (1954–1975).
- Tibet was annexed by the PRC in 1950.