There were many reasons for the fall of the roman empire, but the physical reason was the invasion by several barbarian tribes from the north. what were the names of some of these tribes, and what areas of europe did they conquer
anyone !

The Anglo Saxons.In 476 C.E. Romulus, the last of the Roman emperors in the west, was overthrown by the Germanic leader Odoacer, who became the first Barbarian to rule in Rome. The order that the Roman Empire had brought to western Europe for 1000 years was no more.

Slave labor.  slave labor was an essential part of the economy of spanish polish colonies.