[3] The Ukmergė Old Town contains structure of old streets and squares, also well-preserved buildings of the 19th-20th centuries, therefore it was included in the Registry of Cultural Property of Lithuania.

[6] It is commonly thought that the name may be translated as "she-wolf", from the combination of Vilkas (wolf) and Merga (maiden).

According to local legend, Vilkmergė was a girl raised by wolves, who bridged the divide between animals and humans, in the same way as Rudyard Kipling's Mowgli.

Other historic names for the city include Wilkemerge or Wilkamergen in 1225, Vilkenberge (1333), Wilkinberg (1384, 1455), Vilkomir (1455), Wilkomir (1611), Wilkomirz (1613), Wilkomiria (1766), Ukmerge (1900), Aukmergė (1908); Ūkmergė (1911), Wilkomierz (1918), and Vilkmergė (1919).

The town was granted municipal rights at some time after the Battle of Wiłkomierz in 1435,[9] and written sources dating from 1486 referred to it as a city.

[11] In 1792, by the initiative of the city's representative in the Great Sejm, Józef Dominik Kossakowski, King Stanisław August Poniatowski renewed the town's municipal rights and gave it its current coat of arms.

The future president of Lithuania, Antanas Smetona, was born in Užulėnis near Ukmergė, and was educated in the local school.

In 1919 Bolshevik forces occupied the city during the Lithuanian–Soviet War, but it was soon liberated by the Lithuanian army led by Jonas Variakojis.

In 1930, a monument named Lituania Restituta was erected to commemorate the first decade of restored Lithuanian independence.

After the German invasion, the Nazis rounded up and killed about 10,000 members of the town's Jewish population with the help of Lithuanian collaborators.

Around 1964, two coupled Soviet R-12 Dvina (SS-4) nuclear missile bases were built in the woods near Ukmergė under Nikita Khrushchev.

One of them is a small stone puppy statue named Dog Keksas, to be found in Vienuolyno g. 17 (Ukmerge 20114).