Jacob Palaeologus
Dominican friar who became an anti-Trinitarian

Jacob Palaeologus, also called Giacomo da Chio (c. 1520 – March 23, 1585), was a Dominican friar who renounced his religious vows and became an antitrinitarian theologian. A polemicist against both Calvinism and Papal Power, Palaeologus cultivated a wide range of high-placed contacts and correspondents in the imperial, royal, and aristocratic households in Eastern Europe and the Ottoman Empire; while formulating and propagating a radically heterodox version of Christianity, in which Jesus Christ was not to be invoked in worship, and where differences between Christianity, Islam, and Judaism were rejected as spurious fabrications. He was continually pursued by his many enemies, repeatedly escaping through his many covert supporters.
Palaeologus played an active role in the high politics of European religion and diplomacy over a period of twenty years before he lost imperial favour; and having been extradited to the Papal States, was executed for heresy by the Roman Inquisition.
Life
Palaeologus was born at the Genoese colony on Chios, one of the Aegean Islands near the coast of Anatolia, of a Greek father and an Italian mother. Chios had been, since 1347, ruled by the Republic of Genoa and by the 16th century it was a fief of the Giustiniani family. The young man attached himself to Vincenzo Giustiniani (later Master General of the Dominican Order) and entered into the Dominican Order. He was educated in Dominican schools at Genoa and Ferrara, and later at the University of Bologna. He adopted the name "Jacob Palaeologus" and claimed kinship with the former Palaiologos emperors of Byzantium. Although in later life he repeatedly defended this claim, no independent sources survive that support it.
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The citation trail is more important than the brevity of the summary: it shows where individual claims can be examined in context. The source revision retrieved here is dated Sep 19, 2026. The linked authority identifier is Q3559665. VIAF identifies the subject as 77368077. The Library of Congress control number is n78014927. 2 of 3 selected statements include explicit references; 1 carry qualifiers and 0 use preferred rank. The first chronological checks are 1520, 1585 and 1347.
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This entry incorporates text from “Jacob Palaeologus” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.