Describe the origins and effects of the rivalry between late-medieval Florence and Siena

Please provide the best answer for the statement.

1. The rival cities of Siena and Florence were located in Tuscany: Siena lies in the mountainous southern region of Tuscany, and Florence is located in the Arno River valley.
2. Their rivalry dates back to the contest for supremacy between the pope and the Holy Roman Emperor during the time of Charlemagne, in which one faction, known as the Guelphs, sided with the pope, while another faction, the Ghibellines, sided with the emperor.
Siena was generally considered a Ghibelline city and Florence a Guelph stronghold. By the end of the thirteenth century, the pope retaliated against 3. Siena for its Ghibelline leanings by revoking the city’s papal banking privileges and conferring them instead on Florence.
4. As a result, by the fourteenth century, Florence would become the principal economic and political power in Tuscany.