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Thaddeus Kosciuszko

Thaddeus (Tadeusz) Kosciuszko (1746-1817)[1] was a Polish freedom fighter and engineer.  Kosciuszko endeared himself to this country during the American Revolution and later gained even greater recognition in defense of his native Poland.

Kosciuszko, born in 1746, was schooled at the Royal Military Academy in Warsaw and continued his martial training in France, concentrating in artillery and engineering. After he arrived in Philadelphia in 1776 to join the American cause, the Continental Congress appointed him a colonel of engineers. Kosciuszko’s fortifications contributed to an American victory at Saratoga, and he then was assigned to further fortify West Point, a key point of defense on the Hudson River. Here, in addition to defenses, he created a small garden, which is still maintained at the U.S. Military Academy. At the close of the American Revolution, Kosciuszko returned to Poland, where his military leadership would be called upon again in conflicts with Russia and Prussia. Poland eventually was defeated and ceased to exist as an independent nation. Kosciuszko, badly wounded in a 1794 battle, was imprisoned in St. Petersburg, Russia.

Following the death of Empress Catherine the Great, however, her son and successor, Czar Paul I, granted amnesty to the Polish hero in 1796. According to tradition, he gave Kosciuszko his own fur cloak as a parting gift. In exchange for his freedom and that of other Polish prisoners, Kosciuszko promised not to return to Poland, and arrived in Philadelphia in August 1797. It was there that he and Jefferson formed a strong and lasting friendship. Even though Kosciuszko would remain in the United States for less than a year before returning to Europe, the correspondence between him and Jefferson continued for over 20 years until Kosciuszko’s death in Switzerland in 1817.

When Jefferson was elected president in 1800, Kosciuszko wrote: "Do not forget in your post be always [a] virtuous Republican with justice and probity without pomp and ambition in a word be Jefferson and my friend." During his presidency Jefferson was cautious in his letters, but following his retirement wrote much more freely of U.S. national events, telling Kosciuszko: “The tree which you had so zealously assisted in planting you cannot but delight in seeing watered and flourishing.”

It was upon leaving the United States for the last time that, according to Margaret Bayard Smith’s account, “Kasioskio left his cloak, with his revered friend Jefferson.” This gesture reflected a mutual admiration, as Jefferson had written earlier of Kosciuszko: “He is as pure a son of liberty as I have ever known.”


  1. This article is based on Gaye Wilson, "Thaddeus Kosciuszko, Son of Liberty," Monticello Newsletter 12 (Winter 2001).

Further Sources

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