Early Middle Ages
In ancient history, the Western Roman Empire ruled much of Europe.  Eventually, that empire started to weaken.  In 410, Rome was sacked by Alaric, the leader of the Germanic tribe known as the Visigoths.  Rome survived, but had been weakened greatly.  In 476, when Rome was again invaded and sacked  by Odoacer, he was able to take the city for himself.  He made himself the king of Italy.  This ended the Western Roman Empire.  Europe entered the Early Middle Ages.