Largest empire

1. British Empire - 36.6 million km² (under King George V in 1922)
2. Mongol Empire - 33.2 million km² (under Kublai Khan in 1268)
3. Russian Empire - 22.8 million km² (under Nicholas II in 1895)
   Spanish Empire - 19 million km² (under King Charles III r. 1759-1788)
4. Umayyad Arab Caliphate - 13.2 million km²[1] (under Hisham ibn Abd al-Malik r. 723-743)
5. French Empire - 12.5 million km² (under President Albert Lebrun in 1938)
   Qing Empire - 12 million km² (under Emperor Qianlong)
6. Portuguese Empire - 10.4 million km²
   American Empire - 10 million km² (1898-1934)
7. Rashidun Arab caliphate - 9 million km² (under Caliph Uthman Ibn Affan r. 644-656)
8. Brazilian Empire - 8.1 million km²
9. Achaemenid Persian Empire - 7.5 million km² (under Darius the Great)
10. Japanese Empire - 7.4 million km² (during World War II, under the Showa Emperor)
11. Ming Empire - 6.5 million km² (under the Jingtai Emperor in 1450)
12. Han Empire - 6 million km²
13. Roman Empire - 5.7 million km² (under Emperor Trajan)
14. Ottoman Empire - 5.5 million km² (under Mehmed IV in 1680)
15. Macedonian Empire - 5.4 million km² (under Alexander the Great)
16. Tang Empire - 5.4 million km² (under the Xuanzong Emperor in 715)
17. Maurya Empire - 5 million km² (under Ashoka the Great)
18. Mughal Empire - 5 million km²(under Aurangzeb in 1690)
19. Mexican Empire - 4.5 million km²
20. Byzantine Empire (under Justinian I) - 4.5 million km²
21. Timurid Empire - 4.4 million km²
22. Hunnic Empire - 4 million km² (under Attila the Hun in 441)
23. Seljuq Empire - 3.9 million km²
24. Seleucid Empire - 3.9 million km²
25. Italian Empire - 3.8 million km² (during World War II)
26. Dutch Empire - 3.7 million km²
27. Nazi German Empire - 3.6 million km² (during World War II)
28. German Empire - 3.5 million km² (under Wilhelm II before WWI)
29. Gupta Empire - 3.5 million km² (under Chandragupta II in 400)
30. Sassanid Persian Empire - 3.5 million km² (under Khosrau II in 626)
31. Ghaznavid Empire - 3.4 million km²
32. Afsharid Empire - 3.23 million km² (under Nadir Shah)
33. Pala Empire - 3.2 million km² (under Devapala)
34. Delhi Sultanate - 3.2 million km²
35. Khazar Empire - 3 million km²
36. Safavid Empire - 2.85 million km²
37. Parthian Empire - 2.84 million km² (Under Mithridates II 123–88 BCE)
38. Median Empire - 2.8 million km²
39. Chola Empire - 2.6 million km² (under Rajendra Chola I)
40. Denmark-Norway - 2.6 million km²
41. Belgian Empire - 2.5 million km²
42. Qajar Empire - 2.3 million km²
43. Incan Empire - 2 million km² (Under Atahualpa in 1532)
44. Songhai Empire - 1.4 million km² (in 1500)
45. Neo-Assyrian Empire - 1.4 million km²
46. Aksumite Empire - 1.25 million km²
47. Srivijaya Empire - 1.2 million km²
48. Frankish Empire - 1.2 million km²
49. Sohai Empire - 1.12 million km² (under Buddha Yodfa Chulaloke in 1782)
50. Mali Empire - 1.1 million km²
51. Swedish Empire - 1.1 million km²
52. Maratha Empire- 1 million km²
53. Harsha Empire - 1 million km² (under Harsha Vardhana in 648)
54. Egyptian Empire - 1 million km²
55. Almoravid Empire - 1 million km²
56. Khmer Empire - 1 million km²
57. Polish-Lithuanian Commonwealth - 990,000 km² (under Sigismund III in 1619)
58. Grand Duchy of Lithuania - 930,000 km² (under Vytautas the Great in 1430)
59. Bulgarian Empire - 700,000 km² (under Tsar Simeon I)
60. Austro-Hungarian Empire - 676,615 km²
61. Akkadian Empire - 650,000 km²
62. Durrani Empire - 600,000 km²
63. Neo-Babylonian Empire - 500,000 km²
64. Armenian Empire - 400,000 km²
65. Vijayanagara Empire - 360,000 km²
66. Serbian Empire - 200,000 km²
    

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