[2] The oldest permanent human settlements in the present-day Pleszew and its surroundings date back to the 9th century BC.

King John I Albert in the privilege of 1493 permitted the organization of two weekly markets and two annual fairs.

[3] After the successful Greater Poland uprising of 1806, it was regained by Poles and included within the short-lived Duchy of Warsaw, before it was re-annexed by Prussia in 1815.

[3] In the following decades, to resist Germanisation, Poles founded various organizations, including agricultural, industrial and educational societies, the Cooperative Bank (Bank Spółdzielczy), a printing house, scout troops and a local branch of the "Sokół" Polish Gymnastic Society.

[10] On the day of the German invasion of Poland (World War II), on September 1, 1939, Germany unsuccessfully air raided Polish military barracks, killing 13 civilians instead.

During the German occupation of Poland, the Polish population was subject to mass arrests, executions and expulsions.

[19] The town was captured by the Soviets in January 1945, and was soon restored to Poland, although with a Soviet-installed communist regime, which then stayed in power until the Fall of Communism in the 1980s.

[9] In August 1980, workers of the local automatic lathe factory joined the nationwide anti-communist strikes,[21] which led to the foundation of the "Solidarity" organization.