Original: Cosimo I de 'Medici (12 June 1519 - 21 April 1574) was Duke of Florence from 1537 to 1574, reigning as the first Grand Duke of Tuscany from 1569.
Simplified: Cosimo I de 'Medici (12 June 1519 â "21 April 1574) was Duke of Florence from 1537 to 1574 and then the first Medici Grand Duke of Tuscany from 1569.