Cosimo I de' Medici began ruling dynasty

It is the birthday of Italian Grand Duke Cosimo I de’ Medici (1519), who is credited with doubling the size of Florence and its Tuscan territories and his lavish support of the arts. His idea of uniting the public offices into a single building, the Uffizi (“Offices”), was well ahead of its time. Today the Uffizi Gallery is home to one of the most important art collections in the world. Cosimo became Duke at the age of 17 after his distant cousin was assassinated. With the help of emperor Charles V, he managed to stabilize a rocky political crisis and establish a ruling dynasty that lasted for 200 years. His son, Fracesco de’ Medici, succeeded him.