Leszno , Ger. Lissa, town (1993 est. pop. 59,500), Wielkopolskie prov., SW Poland. A railway junction, it is a center for metallurgy and light industry. Chartered in 1547, it passed to Prussia in 1793 and again in 1815. It reverted to Poland in 1919. Leszno was a center of the Protestant Reformation of the 16th cent. and the chief seat of the Moravian Brethren in Poland. John Amos Comenius was a rector of the famous Moravian school here. The town has an 18th-century palace.