CYRIL I (1570/2–1638), surnamed Loukaris, known also as Cyril Lucar; Greek Orthodox patriarch of Constantinople. Next to Gennadios Scholarios, the first patriarch after the fall of Constantinople, Cyril was the most brilliant and influential head of the Greek church during the period of Turkish rule. Living at a time of intense conflict, when both Rome and the Protestants were seeking to bring Greek Orthodoxy under their control, Cyril strongly favored the Protestant side.

He was born at Candia (modern-day Heraklion) in Crete, then under Venetian sovereignty, and was given the baptismal name of Constantine. He studied at Venice under the celebrated Greek scholar Maximos Margounios, and then at the University of Padua. At his ordination (c. 1593) to the diaconate in Constantinople by Meletios Pegas, patriarch of Alexandria, who was probably his relative, Loukaris took the new name of Cyril. In 1594 he was sent to Poland to strengthen...