The city of Florence is really where the Renaissance began. In those days, Italy was not one single country. It was lots of little states, all governed in different ways and all fighting or making allies with each other all the time.
Rome was politically powerful because Rome had the Pope, the person in control of the Roman Catholic Church. Because of his very great importance as a spiritual leader, most people and most cities did not want to argue with the Pope, whichever Pope he might be. Because a new pope was elected when the old one died, everyone who was rich and powerful was always hoping it might be a member of their family. It was always a good idea to have several young men in the family trained as priests, just in case. It was also a good idea to be good friends with other rich families. One way to do this was to have lots of daughters and get them to marry rich powerful men from different cities. This was the way that politics worked.

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