They had a close connection with the Catholic Church, Frederico's uncle Bartolomeo Cesi was a cardinal in the church, and most of their wealth came from that connection.[1] Federico was the first of eleven legitimate male children and was born in Palazzo Cesi, in via della Maschera d'Oro, Rome, on 26 February 1585. His father was Federico, marchese di Monticelli (1562–1630)[2] and his mother was Olimpia Orsini of Todi. In 1614 Cesi was married to Artemisia Colonna, the daughter of Francesco, principe di Palestrina; she died two years later.