Grand duke of Tuscany in the context of Duke of the Florentine Republic

Cosimo I de' Medici (12 June 1519 – 21 April 1574) was the second and last duke of Florence from 1537 until 1569, when he became the first grand duke of Tuscany, a title he held until his death. Cosimo I succeeded his cousin to the duchy. He built the Uffizi (office) to organize his administration, and conquered Siena to consolidate Florence's rule in Tuscany. He expanded the Pitti Palace and most of the Boboli Gardens were also laid out during his reign.

Gian Gastone de' Medici (born Giovanni Battista Gastone; 25 May 1671 – 9 July 1737) was the seventh and last Medicean grand duke of Tuscany.

He was the second son of Grand Duke Cosimo III and Marguerite Louise d'Orléans. His sister, Electress Palatine Anna Maria Luisa, arranged his marriage to the wealthy and widowed Anna Maria Franziska of Saxe-Lauenburg in 1697. The couple despised each other and had no children. As Grand Prince Ferdinando, Gian Gastone's elder brother, predeceased Cosimo III, Gian Gastone succeeded his father in 1723.