Cosimo II de' Medici, Grand Duke of Tuscany (d. 1621)
Cosimo II de' Medici (12 May 1590 – 28 February 1621) was Grand Duke of Tuscany from 1609 until his death. He was the elder son of Ferdinando I de' Medici, Grand Duke of Tuscany, and Christina of Lorraine.

For the majority of his twelve-year reign, he delegated the administration of Tuscany to his ministers. He is best remembered as the patron of Galileo Galilei, his childhood tutor.