He was present, but did not vote, in the conclave of September 1378 which elected Antipope Clement VII; Clement's election began the Western Schism. He joined the obedience of Antipope Clement VII, and participated in the conclave of 1394, which elected Antipope Benedict XIII. He died in Avignon in August 1405 at the age of 70; at that time, he was Cardinal-Bishop of Porto e Santa Rufina (since 1374). Amerigo (1411) was the first arch-bishop of Florence. At the end of the 15th century the political influence of the Corsini family decreased, mainly because of the seizure of power carried out by the Medici family. Though some of the Corsinis opposed the Medici, the family as a whole continued to flourish in business and politics under Medici rule, acquiring titles, lands, and offices. Filippo (1538–1601) and Bartolomeo (1545–1613) consistently increased the wealth of the family thanks to their large and well organised web of commercial desks around Europe. It was connected with a very fast private postal service (a letter of Bartolomeo, who lived in London, would need less than 3 days to reach Florence). They developed a large banking and brokerage business. They were also responsible for the construction of Palazzo Corsini on the Lungarno; the palace was built in what is now referred to as ‘Florentine Baroque’ style. The two Florentine Palazzos – one on the Lungarno and the other in Via del Prato – mark the intensifying relationship between the family and the art world in the course of the 17th century. The chapel in the Chiesa del Carmine, dedicated to Sant’Andrea Corsini, was built during the first half of the century. The Galleria Gentilizia, where many works of art were preserved, was developed in the Palazzo which dominates the Arno river. Their cousin, Cardinal Ottavio, hosted a musical drama in 1620 on his palace. Some professors argue that this is the first time a lyrical opera was staged. During those years, the Corsinis were granted the feuds of Sismano, Casigliano and Civitella. In 1620, Paolo V (Pope Paul V) granted them the title of Marquis of Sismano, which was extended by Urbano VIII (Pope Urban VIII) to and Civitella (1629), later Lajatico and Orciatico (1644) and finally and Tresana (1652).