When Did the Mongol Empire Peak?

Genghis Khan united the Mongol tribes in 1206 and launched rapid conquests across Central Asia, Persia, and into Eastern Europe. His grandsons continued the expansion: Batu Khan invaded Russia and Hungary in 1237-1242, and Kublai Khan conquered Song Dynasty China by 1279, establishing the Yuan Dynasty. At its peak, the empire stretched from Korea to Hungary and from Siberia to Vietnam, encompassing roughly 24 million square kilometres and about 100 million people (25% of the world population). The empire facilitated the Pax Mongolica — a period of relative stability along the Silk Road that boosted trade between East and West. However, the vast empire was already fragmenting into four khanates (Yuan, Chagatai, Golden Horde, Ilkhanate) by the late 13th century, as succession disputes and the challenge of governing diverse territories took their toll.