A town of Russian Poland, capital of the government of the same name, and formerly the seat of the high court of Poland, on the railway from Warsaw to Vienna, 90 m. southwest of the former and 5 m. west of the river Pilica. Pop. (1900), 32,173. It is a well-kept town, with numerous gardens, and has flour-mills, saw-mills, tanneries, agricultural machinery works, and breweries. One of the oldest towns in Poland, Piotrkow was in the 15th and 16th centuries the place of meeting of the diets, and here the kings were elected. In the 14th century Casimir the Great built here a castle (now a military church) and surrounded the town with walls. Here in 1769 the Russians defeated the (Polish) forces of the Bar Confederation.