The tribe that sacked Rome in 410 AD under the leadership of Alaric I was the Visigoths. Alaric I was the king of the Visigoths, a Germanic tribe that played a significant role in the decline and fall of the Western Roman Empire. In 410 AD, the Visigoths, led by Alaric I, successfully captured and sacked Rome, marking a significant event in the history of the Roman Empire.