Why do you think three ancient societies considered as the cradle of civilization

ancient rome, china, and sparta

Explanation:

the dust bowl, otherwise known as the dirty thirties, was a huge dust storm that killed multiple (and i mean  multiple) farmer's crops, leaving them homeless, and foodless, and jobless. in california, there were 5.7 million residents, and the population shrank as mexicans were repatriated. however, when the dustbowl happened, a lot of people began to move to california. by 1940, 250,000 people had arrived. therefore, your answer would be  the population increased, massively.  i hope this !

explanation:

after the roman empire, the catholic church began to unify by taking on many duties of a government.