Name the title given to rulers in Florence, Rome and Venice

The title given to rulers in Florence during the Renaissance period was "Duke" for most of their ruling history, with "Grand Duke" being used after 1569. Notably, the Medici family, who were de facto rulers of Florence as wealthy patrons and politicians, did not always officially hold these titles but were powerful nonetheless.

In Rome, the ruler was often known as the "Pope," especially in the context of the Papal States, which was a series of territories in the Italian Peninsula under the direct sovereign rule of the Pope from the 8th century until 1870.

Venice had a unique title for its ruler – the "Doge." The Doge was the chief magistrate and leader of the Republic of Venice for over a thousand years, with the position being established in the early Middle Ages and lasting until the late 18th century.

Extra: The titles of rulers in historical European contexts often reflected the governmental structure and the cultural heritage of the region. In Florence, the title of Duke or Grand Duke signified a sovereign ruling over a dukedom or grand dukedom. The Medici family's influence exemplifies how power could also be exercised through wealth and patronage, not just formal titles.

In Rome, the Papacy was both a religious and political position. The Pope, as the Bishop of Rome, is the head of the Roman Catholic Church; however, during the time of the Papal States, the Popes also possessed temporal or secular power much like a king or prince would elsewhere.

As for Venice, the term "Doge" is derived from the Latin "Dux," meaning leader. The position was elective and the Doge was usually chosen for life by Venice's aristocracy. The system in Venice was known for its complex checks on the Doge's power, reflecting the republic's dedication to preventing any single individual from gaining despotic control. Each of these roles had significant influence on the political, social, and cultural landscape of their respective city-states and territories, and they are emblematic of the diverse forms of governance that existed across Europe throughout its history.