During the reign of Sigismund II Augustus, Leżajsk prospered due to protection of its starosta (local governor), Krzysztof Szydłowiecki (Odrowaz coat of arms), who was Crown Chancellor.

In 1608, Bernadine monks from nearby Przeworsk were brought to Lezajsk by Bishop of Przemyśl, and two years later, the first brick church was built.

In 1624 Lezajsk was looted and burned by Crimean Tatars and the subsequent Swedish invasion of Poland (1655–1660) brought more destruction.

During the German invasion of Poland, which started World War II, on September 13, 1939, Leżajsk was captured by the Wehrmacht.

[3] On November 3, 1939, the German security police carried out mass arrests of local Poles as part of the Intelligenzaktion.

The Jewish cemetery in Leżajsk is a place of pilgrimage for Jews from all over the world, who come to visit the tomb of Elimelech, the great 18th century Hasidic Rebbe.

[7] From the early 1500s until the advent of World War II and the Holocaust, there was a major Jewish presence in Leżajsk.

[9] When Nazi Germany invaded Leżajsk in September 1939, almost all Jews in the town were brought to the Soviet-Occupied zone, where they were later massacred by the Einsatzgruppen.