Following the demise of Batu Khan, the helm of the Golden Horde, in 1255, his lineage flourished for a century, until the intrigues of Nogai ignited internal strife in the late 1290s, leading to a partial civil conflict. Under the reign of Uzbeg Khan (1312–1341), who embraced Islam, the military prowess of the Horde reached its zenith. The territorial expanse of the Golden Horde at its pinnacle encompassed Siberia, Central Asia, and Eastern Europe, spanning from the Urals to the Danube in the west and from the Black Sea to the Caspian Sea in the south. It bordered the Caucasus Mountains and the domains of the Ilkhanate.