KOŚCIUSZKO, TADEUSZ. - Polish patriot, b. at Mereczowszczyzna on 4 Feb. 1746, d. at Solothurn (Switzerland) on 20 Oct. 1817. Protected by the Czartoryski family, he was able to attend the cadet school in Warsaw, leaving it as an officer. He then perfected his training in Paris, where, in the Enlightenment climate of the French capital, those democratic-humanitarian ideas took root in him, that faith in progress and in the improvement of humanity which never afterwards left him.
Sentimental complications led him to the United States (1776), where he enlisted as a colonel of engineers, distinguishing himself by his moral qualities and technical ability, so much so that he reached the rank of commander-in-chief of the engineers' corps of the southern army. His stay in the United States and his contact with American society strengthened in him his already clear democratic conscience.
Thus, after his return to his homeland (1784), in the aftermath of the unhappy campaign of 1792 against the Russians and of the second partition of Poland, K. appeared to all those who yearned for recovery as the person best suited to channel toward a single goal, the struggle against the Russians, all the social classes. On 23 March 1794 K. took command at Kraków of the insurrection, which spread throughout all Poland and won successes at Racławice, in Samogitia, at Warsaw and at Vilnius, while by timely measures in favor of the peasants (partial abolition of serfdom, reduction of the corvées for the fighting peasants, etc.) he managed to bring fresh forces into the ranks of the insurgents. The Russians under Suvorov, after the reverses they had suffered, took the offensive and together with the Prussians under Fersen defeated the Poles in the successive battles of Szczekociny (6 June) and Maciejowice (10 Oct.), where K., gravely wounded, fell into the hands of the Russians, while on 4 Nov. Warsaw capitulated. K., taken as a prisoner to St. Petersburg, was set free by Paul I at the end of 1796 and from then on remained practically inactive and politically isolated, except for a last conversation in 1815 with Alexander I, retiring to Solothurn.