I cant find one word about the Southern Kingdom (sometimes called the kingdom of Sicily or Naples)
I occasionally hear something about Genoa, the Pope, and Venice. Tuscany maybe. It seems the first abolition were against western Christians owning western Christian slaves, but everything was fine
I know Florence had a doge who was the son of a Medici and a black slave, but the overwhelming majority of Slaves we're east European or Mediterranean.
Are there no records of any abolition? Did they not sign on to those organisations the british started after 1833 to end slavery?
Just as a heads up: The ruler of Florence was never called "Doge," in the Republican period.
Generally, Italian slavers in the middle ages were part of an Italo-Greek cartel transiting non-Christian slaves in the eastern Mediterranean. However, by the mid-tenth century, there were efforts by authorities in cities like Venice to rein in the slave trade, even if there is still a correlation between the distance from nearest Venetian Overseas Consul and participation of Venetians in the slave trade. In 959, Doge Pietro Candiano IV emitted a decree stipulating that no Venetian citizen could lend money to a Greek slave trader, and no Venetian ship would be permitted to transport slaves in Greece. The ban on slave transport was later extended "Ultra Polam" or beyond the Venetian outpost of Pola, fundamentally banning the transport of slaves in Dalmatia, while direct investment in the slave trade by Venetians was also banned in "Terra Beneventi," or the Duchy of Benevento. Although these bans indicate a flourishing trade in Muslim prisoners in Southern Italy and the Byzantine Empire, there is also an uptick of economic activity following Emperor Henry's victories over the Slavs, as Venetians sold prisoners of war captured in central and eastern Europe in the Middle East.
I wrote more on the matter here in great discussion with other users on this sub.