How did Islam expand rapidly after the fall of the Roman Empire?

Question

A. Islamic empires joined together groups of Christians who had been forgotten by the Roman Empire
B. Islamic empires joined together big, expansive kingdoms left in a vacuum of power caused by the fall of the Roman empire
C. Islamic empires joined together nomadic groups and small, local kingdoms that were left in a vacuum of power caused by the fall of the Roman Empire
D. Islam did not expand rapidly after the fall of the Roman Empire

Answer 1

The correct answer is C. Islamic empires joined together nomadic groups and small, local kingdoms that were left in a vacuum of power caused by the fall of the Roman Empire.

After the fall of the Roman Empire, many regions experienced a power vacuum, which allowed for the expansion of Islamic empires. The early Islamic conquests took advantage of the instability and fragmentation in various territories, allowing them to unify and expand by incorporating nomadic groups and smaller, local states into the growing Islamic polity.