Here's a breakdown of the factors:
* Vulgar Latin: The root of Italian, like other Romance languages, is Vulgar Latin. This was the spoken Latin of the common people, distinct from the more formal Classical Latin.
* Regional Dialects: Vulgar Latin evolved into different regional dialects throughout Italy. These dialects were influenced by local languages, cultures, and interactions with other groups.
* Florence and Tuscan Dialect: The Tuscan dialect, specifically the Florentine variety, gained prominence during the Renaissance. This was partly due to the influence of great Florentine writers like Dante, Petrarch, and Boccaccio, who wrote in the Tuscan dialect.
* Standardization: The Tuscan dialect, with its literary prestige, became the foundation for a standardized Italian language. This process was further influenced by the political unification of Italy in the 19th century.
So, while Florence played a crucial role in the development of Italian, it wasn't the sole birthplace. Italian's origins lie in the confluence of various regional dialects and the standardization process that eventually led to the modern language we know today.