Only archaeological findings provide information about the first residents of the territory of the town of Ukmergė. They testify that people settled in this territory around 11th century. 1333 is the official date of the foundation of Ukmergė. That was the year when Ukmergė was first mentioned in written documents, i.e. in the chronicle of Hermani de Wartberge. In the 14th century Ukmergė was mentioned among contemporary towns – castles. It is supposed that the Magdeburg rights were conferred on the town in 1435. In 1554 there were 500 residents in town. In 1595 Ukmergė was first marked on the map of the Great Duchy of Lithuania. Most buildings of the town were wooden, therefore Ukmergė suffered from fires time and again. The first Jews started settling in Ukmergė around 1674. Since then their population was growing constantly so from the beginning of 19th century till World War I Jews constituted the majority of Ukmergė residents. On 22 May 1792 Ukmergė regained the town laws. In 1812 there were about 1900 town residents. In 1847 Ukmergė became the town of the County of the Russian Empire with appropriate rights. Two huge annual fairs and one market per week took place in the town. At the end of 19th century the town began decreasing. At the end of 1918 local authorities and institutions of the Republic of Lithuania began to be established in town. With gradual strengthening of the Lithuanian state, the town also revived. The three largest national diasporas: Lithuanians, Jews and Poles got along with each other. Each of them had their own representatives in local authorities, educational institutions and public organizations which represented versatile cultural and social life. Ukmergė was the centre of the county and the fourth largest town in Lithuania. The composition of town dwellers changed strongly because of Nazi and Soviet occupations – the community of Jews was killed; the major part of the intelligentsia moved to the West or was exiled. Rural inhabitants, terrified by the soviet collectivization, moved to town. In 1950 the county of Ukmergė was abolished. The monument “Lituania Restituta”, built for 10th anniversary of the independence of Lithuania, was demolished in 1951; the cemetery of Jews was tread by bulldozers. The Holy Trinity Church was transformed into a storehouse; the Great Jews synagogue was replaced by the sport school.
Ukmergė developed as a small industrial centre. The town grew and expanded: there were 14 900 residents in 1959 and 21 600 in 1970. In October 1988 the National flag was raised above the Culture Centre of Ukmergė. On 16 February 1990 the monument “Lituania Restituta” was rebuilt. 57 deputies, formally the members of Council of new and independent Republic of Lithuania, were elected in the elections which took place on 23rd March of the same year. A long and difficult way of restoration of the Lithuanian state and self-government of the district as well as of economic reform and creation of civil society started.