The histories of particular cities and states within that myriad-faceted slice of civilisation, the Renaissance in Italy, have received more scholarly attention than have the diplomatic, ecclesiastical and cultural connections between them. This study is part of a balance-redressing process. Senior clerics traversed frontiers, owing allegiance to their native state, their benefices and, above all, to the Papacy. The purpose of this exploration of the curial careers of four later quattrocento Venetian cardinals is essentially twofold : to account for relations between Venice and the Papacy with reference to individuals who were at once Venetian patricians and princes of the Church; and to examine the cardinals' responses to this situation in terms of political, ecclesiastical and cultural patronage. Where did their loyalty lie? To Venice, with its perennial suspicion of the Church and peculiar notion of the characteristics of a Venetian cardinal? Or to the Pope, expressing overt hostility towards the Republic in the War of Ferrara and placing it under an interdict? Chapter one sets Merco Barbo, Pietro Foscari, Giovanni Michiel and Giovanni Battista Zeno in a Venetian context. Chapters two and three chart relations between the two powers, from the exposure of Cardinal Zeno's involvement in a scheme to transmit Venetian state secrets to Rome in exchange for ecclesiastical preferment, through to Ermolao Barbaro's controversial appointment to the patriarchate of Aquileia, via the short-lived Papal-Venetian league negotiated by Cardinal Foscari in 1480. The fourth chapter considers their proximity to the Supreme Pontiff and how their material fortunes varied under popes Sixtus and Innocent, after which an assessment of the nature, extent and effectiveness of their patronage is divided between chapters five and six, focussing pa.rticularly on Venetian connections. Despite diverging careers, it is concluded that all were bound by variations of the Venetian inheritance.