Pope (1431-1447), original name Gabriel Condulmaro.
Born in Venice in 1383, Gabriel became pope in succession to Martin V. He continued ecumenical negotiations with the Byzantines, even agreeing to hold a council in Constantinople. He brought Emperor John V Palaiologos, along with the patriarch of Constantinople and 700 of their supporters, to Ferrara for an ecumenical council beginning 8 January 1438. However, the expense of hosting his Byzantine guests, plus a revolt in Rome, nearly bankrupted him. On 10 January 1439 the council moved to Florence, and on 6 July the union of the Latin and Greek Orthodox churches was proclaimed, followed soon after by similar agreements with the Armenians, Nestorians, and Maronites of Cyprus. The Byzantine reward for the union was help to defend Constantinople, but the crusade of 1444, after a few successes, was defeated at Varna in Bulgaria and did little to protect the empire. Simultaneously, Eugenius was struggling with the Council of Basel, a majority of whose members refused to join the Council of Ferrara-Florence. They deposed him on 25 June 1439, electing Felix V as antipope, which lost the council much of its support. Eugenius continued his policies with widespread support, dying on 23 February 1447.