What is one of the Northmen who founded a dynasty in Russia in the 9th century; also, one of the Northmen composing, at a later date, the imperial bodyguard at Constantinople called?

varangian — One of the Northmen who founded a dynasty in Russia in the 9th century; also, one of the Northmen composing, at a later date, the imperial bodyguard at Constantinople. (Webster's 1913.)

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