In the West, Pope Eugenius IV conducted further negotiations in an attempt to extend the union. He signed an agreement with the Armenians on 22 November 1439, and with a part of the Jacobites of Syria in 1443, and in 1445 he received some of the Nestorians and the Cypriot portion of the Maronites. These unions proved unstable and mostly failed to last. In the spring of 1442 the Papacy began planning a crusade by both land and sea against the Ottomans from Hungary and the Mediterranean to fulfil the Pope's pledges. These plans were initially slowed by a civil war in Hungary. On 1 January 1443, Eugene IV finally proclaimed an official crusade. Władysław III of Poland, now King of Hungary as well, agreed, but could not find support among his Polish nobles because they supported the Conciliar Movement against the Pope. Władysław nonetheless undertook the crusade with Hungarian troops and was killed in the Battle of Varna within a year, ending the attempt. Constantinople could no longer expect the West's military support.