What was the main acheivement of genghis khan and the mongols?

The unification of Mongolia and the invasion and domination of China.

Explanation:

The Mongol Empire is considered to be one of the largest in history in continuous land extension: it ranged from the western border of Germany to the Korean Peninsula, and from the Arctic Ocean to Turkey and the Persian Gulf, dominating about a third of the population total of the planet at the time. It began in 1206, when a warrior named Temujin was proclaimed Genghis Khan, the supreme sovereign of Mongolia. Using strategies of war and politics, the leader was responsible for the unification of the numerous nomadic tribes that inhabited the region and resembled customs and language.

After the unification of Mongolia, Genghis Khan's first target was China. Armed with a skillful, organized and disciplined army, he crossed the Great Wall and surrendered Beijing in 1215. Between 1221 and 1225, in unceasing campaigns, the Mongols advanced upon the Muslim states and became masters of an empire that stretched as far as the Persian Gulf

2: albert einstein was one of several german scientists who the allies defeat the nazis

explanation:

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