Short answers, pulled from the story.
The Medici family was first mentioned in a document from 1230 located in the Mugello region north of Florence. They began as farmers before entering the wool trade with France and Spain during the early 14th century.
Giovanni di Bicci de' Medici founded the Medici Bank in 1397 to manage their growing wealth. This institution became Europe's largest bank by the mid-15th century using double-entry bookkeeping for the first time in business history.
Cosimo returned to Florence in 1434 after being exiled the previous year by rival families like the Albizzi. He gained popular support through a proportional tax system despite never holding political office while becoming the unofficial head of the Florentine Republic.
Four popes emerged from the Medici line including Leo X who reigned from 1513 to 1521, Clement VII from 1523 to 1534, Pius IV from 1559 to 1565, and Leo XI in 1605. These pontificates coincided with Martin Luther's Protestant Reformation and the sack of Rome in 1527.
The Medici dynasty ended when Gian Gastone de' Medici died in 1737 after ruling from 1723. The treasury was virtually bankrupt by 1705 when Cosimo III tried to negotiate settlements with European powers.