Sure, I can try. Italy what’s not a thing, whatsoever. It was, as Metternich will say in the XIX, a geographical expression.

They were nominally part of the Holy Roman Emperor in the north, were a network of dukes, counts, republican magistrates (like Doges) or consuls we’re. They will not hold any king title or pretension because they were supposedly subordinate to the emperor, but they were actually independent.

We had two kinds of government structures in northern Italy, feudal nobility holdings like Ferrara or republican city states like Siena, Florence or Venice. But it worked pretty similar to the Greek polis. Cities that will be encapsulated in themselves, governing territories in the name of the main polis and dominating each other through trade, alliances and leagues rather than direct control and occupation.

It was also flawed in the same way because each city will have to main dominant classes (the old watch nobility and the new rich patricians) that will fight each other for controlling the city and also they will compete with the other cities for prestige, glory and money. Because of that in Italy it was a profitable business to maintain a warband of mercenaries that will be available each time any city will go to war, and just fight for the one who paid more (the Condottieros)

Thing is that, as this cities didn’t have an standing army besides city watch, they’ll become an easy prey for the heavily armed condottieros who will seize the power time to time (Ludovico Sforza in Milan)

And when they did not involve the Condottieros, the will go straight for a foreign potency to involve so they can achieve their cities supremacy. France and Spain mainly.

That situation didn’t, nevertheless, originated in the renaissance. As early as the 13 century Dante will beg for a powerful and universal monarch that will finally appease Italy. But it will reach top peak in the XV-XVI centuries.

As for southern Italy, the Pope will rule the Papal States that will extend from Rome and Lazio Area to even Romagna and Friuli. Normally respected because of being the church head, sometimes will also incur in the same dynamics than the north, like when Pope Alexander VI was going to be “deposed” by the French King at instance of a rival Cardinal.

The only state we have left is Naples/Sicily. Since the normans recognized as a monarchy, it’s going to become the punching ball for France and Aragon (later Spain) because of dynastic rights. Both king will claim the sovereignty over Naples, and the Pope will always be the referee. That will allow pipes to become friend with each potency when they need it, specially in the times it developed as an “independent Kingdom” nominally subject of the pope.

After a century of war in the late XV and Early XVI centuries, will be secured and holt by Spain.