[2] Folk etymology also relates the name to the word širvis, which is used to refer to a moose because of the colour of its fur.

In 1746, the ruler of the Polish-Lithuanian Commonwealth, Augustus III, granted permission to Mykolas Eperješas, the Elder of Širvintos, to organise weekly markets and fairs.

In 1830-1831, during the November Uprising that swept across the former Commonwealth, the rebel government of Vilnius County was established in Širvintos.

During the January Uprising of 1863-1864, the rebels in Širvintos destroyed the records and documents belonging to the Russian authorities.

Following a series of intense clashes during the Battle of Giedraičiai, the Polish army was ultimately forced to retreat.

[8] In September 1941, Jews of the town are murdered in mass executions perpetrated by Germans and Lithuanian collaborators.

[9] On 6 October 2016, a monument to Ignas Šeinius, a writer and diplomat hailing from Širvintos, was inaugurated in the town's central avenue.

[10] In June 2024, a monument to a poet and playwright Justinas Marcinkevičius was unveiled in the Youth Garden of Širvintos.