Largest contiguous empire

The largest connected empire to have ever existed was the Mongol Empire of 1206–1368, ruled by the Khan Dynasty. At its peak in the late 13th century (circa 1279) under Kublai Khan, the empire ruled over 110 million people (about one-quarter of the global population) living across an area of 24 million km² (9.3 million sq mi) including the present-day regions of China, Russia, Mongolia, Central Asia, the Middle East and the Korean Peninsula.

Kublai Khan was the grandson of Ghengis Khan (who founded the Mongol Empire in 1206).

Some sources cite 1405 as the demise, however, most historians agree that from 1368 onwards the Mongol Empire began to fragment and decline, with the ascendancy of the Ming Dynasty in China.

The second-largest contiguous empire was that of Russia which, at its peak (c.1895), covered an area of some 22.8 million km² (8.8 million sq mi). The largest-known empire overall (albeit not contiguous) was the British Empire, which in 1920 comprised an area of approximately 35.5 million km² (12.9 million sq mi) – about one-quarter of the total land surface on Earth.