Which group destroyed cities, looted treasures, and killed thousands in russia during the thirteenth century? a. boyars b. vikings c. mongol tartars d. slavs

The Mongol Tartars invaded Russia in the 13th Century (1200's), and they killed between a quarter and a half of their total population. The Mongol's that invaded Russia had armies of nearly two million people, meaning that it was difficult for some of the smaller towns to stop the invasion.
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In 911, a group of vikings lead by rollo besieged paris and chartres. after a victory near chartres on 26 august, charles decided to negotiate with rollo. the talks were led by hervé, the archbishop of reims. this resulted in the treaty of saint-clair-sur-epte, which granted rollo and his soldiers all the land between the river epte and the sea. it also granted him brittany, "for his livelihood". at the time, brittany was an independent land which france had not been able to conquer. in exchange, rollo promised the king his loyalty and military assistance when needed. also rollo also agreed to be baptised and to marry gisela, the king's daughter. the territory given rollo is about the same as upper normandy.