I think there could be a couple terms you could use to answer that question. One might be fractious -- lots of friction and competition for power. As a result, certain nobles would position themselves to become "Signori" or lords of the cities. As individual noble families took on a larger role of power that way, the Italian city-states also thus became more oligarchic. Oligarchy is a word that comes from ancient Greek, meaning "rule by a few."
