Portrait of Korniakt at prayer 
|Born||Konstantinos Korniaktos (Κωνσταντίνος Κορνιακτός)
Candia, Kingdom of Candia
Lviv, Polish–Lithuanian Commonwealth
|Residence||Lviv, Polish–Lithuanian Commonwealth|
|Other names||Constantine Corniaktos, Kornak, Korniak, Korniat, Korneadi, Korneades, Carneadi, Coretho, Carinacto|
|Known for||Financing the construction of the Korniakt Palace in Lvov Lviv,|
|Children||Alexander Korniakt, Constantine Korniakt, Michael Korniakt, Katarzyna Korniaktówna, Sophia Korniaktówna|
Konstanty Korniakt h. Krucina, also Constantine Korniakt (c. 1517 – August 1, 1603) (Greek: Κωνσταντίνος Κορνιακτός, Konstantinos Korniaktos, also known as Korniat, Korneadi, Korneades, Carneadi, Coretho, Carinacto), was a Greek born merchant, and a Polish nobleman, active throughout Central and Eastern Europe; a leaseholder of royal tolls who collected customs duty on behalf of the king. During his lifetime he was the wealthiest man in Lviv (Lwów, in Polish) and even owned numerous villages. He was a wholesale merchant and founder of the Korniakt family dynasty.
Konstantinos Korniaktos was born of Greek descent, in the city of Candia (Crete) in 1517. He moved to Constantinople at a young age, later migrating to Wallachia where he lived for the rest of his life. He settled in the city of Lviv, where he took over a business of his older brother Michael. The King of Poland Sigismund II Augustus granted him official title of nobility on February 12, 1571 as szlachcic Konstanty Korniakt, also awarded a number of other privileges.
Konstanty Korniakt dealt with international trade, especially from the Ottoman Empire and countries in Germany. He became a merchant and traded in wine, cloth, cotton, honey, hides and furs and soon became very wealthy, even lending money to the kings of Poland including Sigismund II Augustus, and other noble families.
Korniakt was a patron of architecture and built a magnificent house near the market, which later was rebuilt by John III Sobieski and is now known as the Korniakt Palace. He also expanded the Wallachian church and funded its famous tower. He was an ardent follower of the Orthodox Church and defended its interests maintaining friendly relations with other Christian denominations.
Around 1575 he married Anna Dzieduszycka h. Sas, and soon had children. His sons were Alexander, Constantine (father of Captain Charles Francis) and Michael Korniakt, his daughters were Katarzyna Korniaktówna, Anna, whom married Jan "Gratus" Tarnowski, Sophia, who married Abraham Hubert and Catherine, she married Aleksander Chodkiewicz and after his death the governor of Belz, Duke Konstanty Wiśniowiecki.
Constantine Korniakt died in 1603, his son subsequently sold part of his estate an land in Lviv, and his brother Alexander Korniaktow left and moved to the property he inherited from his parents in Przemysl. He was owner of three residences in the villages Sośnica, Złotowice and Białoboki, the latter being chosen for the family. In 1610 the construction of the castle began.
- Krzysztof Bulzacki (2007–2012). "Rody Lwowskie - część I (Lwow noble families - part one): Konstanty Korniakt (1520–1603)". Alembekowie, Boimowie, Korniaktowie, Kampianie, Barączowie, Baczewscy (in Polish). Stanisław Kosiedowski - Mój Lwów. Retrieved 10 July 2013.
- Polska Akademia Umiejętności (1969). Polski słownik biograficzny, Volume 14. Instytut Historii PAN. p. 82. OCLC 309990360. "(Korniat, Korneadi, Korneades, Carneadi, Coretho, Carinacto) Konstanty h. Crucini (ok. 1520 — 1603)"
- Malinowski, Jerzy (1993). Where East meets West: portrait of personages of the Polish-Lithuanian Commonwealth, 1576-1763 : exhibition catalogue. National Museum in Warsaw. p. 222. ISBN 83-7100-088-X. "Konstanty Korniakt Lwow merchant of Greek origin"
- Adam Bujak, Jerzy Janicki (1997). Lwów. Wydawn. p. 17. ISBN 83-907436-1-2. "Korniaktowska Tower after its founder, a Cretan-born Greek named Korniakt, and classed by connoisseurs without a trace of exaggeration alongside the finest campanillas of Florence"
- Isaievych, Iaroslav Dmytrovych (2006). Voluntary brotherhood: confraternities of laymen in early modern Ukraine. Canadian Institute of Ukrainian Studies Press. p. 47. ISBN 1-894865-03-0. "…the Greek merchants Constantine Korniakt and Manolis Arphanes Marinetos are added. This second redaction appeared no earlier than 1589, as wealthy Greeks began to join the confraternity at a later date, once it had expanded its activities. Korniakt was actually the wealthiest man in Lviv: he traded in Eastern, Western, and local goods, collected customs duty on behalf of the king, and owned a number of villages."
- Panagiōtakēs, Nikolaos (1998). Anthē charitōn: meletēmata heortia sungraphenta. Istituto Ellenico di Studi Bizantini e Postbizantini di Venezia. p. 21. OCLC 301347251. "Κωνσταντίνο Κορνιακτό, ό όποιος τον είχε ..."
- Anna Benn, Hans Hoefer, Dorothy Stannard (1995). Russia: with chapters on Ukraine and Belarus. Apa Publications (HK) Ltd. pp. 306–307. ISBN 0-395-66167-6. ""Korniakt", was also built at the end of the 16th century for a well- known Greek merchant who used his influence to build a specially wide house"
- Vasylʹ Mudryĭ, Naukove tovarystvo im. Shevchenka, Shevchenko Scientific Society (U.S.) (1962). Lviv: a symposium on its 700th anniversary. New York. p. 175. OCLC 3999247. "Foreign merchants who chose Lviv as their second home, repaid the city a hundredfold: the Greek from Crete, called Koreto de Candia, whose name was popularly abbreviated into Korniakt , was the most prominent Ukrainian patrician leader in Lviv in the late 16th and early 17th century, erected a beautiful bell-tower on the pattern of Renaissance campaniles attached to the church of Assumption."
- Beleckij Platon (1960). Le portrait dans la peinture ukrainienne (" Parsuna ") des XVII e et XVIII e siècles. Ecole des hautes études en sciences sociales. pp. 630–636. OCLC 295668339. "bienfaiteur de la Confrérie Constantin Korniaktos, Grec d'origine"
- École pratique des hautes études (France). Section des sciences économiques et sociales (1979). Cahiers du monde russe et soviétique, Volume 20. Mouton. p. 354. OCLC 185427756. "A famous case is Constantine Korniakt at the end of the sixteenth century who was a native of Crete, became a wine merchant in Lvov, was a leaseholder of royal tolls and finally achieved nobility."
- Adam Bujak, Jerzy Janicki (1997). Lwów Львів Leopolis. Wydawnictwo Bosz. p. 17. ISBN 83-907436-1-2. "Korniaktowska Tower after its founder, a Cretan-born Greek named Korniakt, and classed by connoisseurs without a trace of exaggeration alongside the finest campanillas of Florence."
- Victor E. Louis, Jennifer M. Louis (1976). The complete guide to the Soviet Union. M. Joseph. p. 184. ISBN 0-7181-1077-3. "…built by Pietro di Barbona in 1574-80 for a Greek merchant, Constantine Korniakt. who financed the building of several churches in Lvov."