Kėdainiai is one of the oldest towns in Lithuania which is located on the pictorial shores of the river Nevėžis. The town was first mentioned in written sources in 1372 m. According to the legends the town was named after a wealthy merchant Keidangen,  who came from Kuršas and established a small fishing village. In the XV-XVI c. the town grew rapidly and it became one of the first centres of the Reformation of the GDL, as well as the centre of craft and trade. Therefore, in 1590 it was granted the Magdeburg rights.

Since the middle of the XV century Kėdainiai was a private town, ruled by the dukes Radvilos and noblemen Kiškos.  The most important traces in town’s history were left by Kristupas Radvila (1585-1640) and his son Jonušas Radvila (1612-1655). The father and the son took care of the growth and development of the town. They invited foreign craftsmen, engineers, educators to come to Kėdainiai. K. Radvila established a school which later developed into gymnasium where teachers from Western Europe gave lectures. In the Radvilos times, Kėdainiai was known as the centre of craft and trade, as well as the town of many nations and various confessions and cultures. Six ethnic and six confessional communities lived there at that time. One of the largest Scottish community in the Baltic and Scandinavia regions also lived in Kėdainiai. Germans had their own autonomy. A large Jewish community was the biggest in the whole Žemaitija. Gaonas Elijahu (1720-1797), who later became famous all over the world, studied in Kėdainiai Rabbinical School.  In the XIX century the district of Kėdainiai was strongly affected by the Polish culture.

Kėdainiai is one of the seven Lithuania cities having a unique old town. The old town preserved historical streets, four merchant squares, and a number of valuable buildings of XVII-XIX centuries with the elements of Renaissance, Baroque and Classicism.

These days, Kėdainiai is often called the capital of Cucumbers, because of Jews who lived there in the XIX century and started the cultivation of cucumbers. These traditions have still remained and the citizens of Kėdainiai supply cucumbers to many regions of Lithuania. Canned cucumbers are exported to foreign countries.

Every year in July, tourists are attracted by a joyful Cucumber fiesta and in August people celebrate Town's birthday and Ice Cream Festival.