[1] It is believed to originate from the name of a nobleman Chašaidaras, an ethnic Tatar, who was enlisted to the Grand Ducal Lithuanian Army in 1565.

[2] In the area of the present day town, the nobleman had some land and a mansion, referred to by his name, which later became the name of the settlement.

[2] The city expanded when a railroad connecting Vilnius with Liepāja was built in 1871.

During the First World War, the town was occupied by the Germans in 1915, and it became the capital of an administrative unit for the first time.

In August 1941, the Jewish population of the town and surroundings was murdered in mass executions perpetrated by an Einsatzgruppen of Germans and Lithuanian nationalists.