The land which was to become Larsmo rose from the sea some 2,000 years ago, due to post-glacial rebound.

During the dark autumn night of December 6, 1905, the steamer SS John Grafton sailed into the Larsmo archipelago with its cargo of weapons, meant to be used for the independence movement in Finland and the revolutionary attempts in Russia.

The crew fled to Sweden with some smaller sailing vessels and the ship was blown up on December 8.

[9] SS Equity, another ship, loaded with weapons, also unloaded its cargo in the Larsmo archipelago,[10] and a memorial plate is now in place at the Tolvmangrundet island.

Emigrants from Larsmo founded the town of Larsmont, Minnesota, in the United States in the early 1900s.

They originally requested to name the town Larsmo, but railroad officials did not approve and instead chose the name Larsmont.

[13] Prominent religious movements in the region are the Evangelical Lutheran Church of Finland, Laestadianism (the Word of Peace tendency), as well as a smaller number of Baptists.

[14] Larsmo has traditionally had the country's highest fertility rate – 3.4 in a 2013–2015 study[15] – due to the influence of Laestadianism.

The previously mentioned Bjärgas hembygdsgård is an open-air museum portraying rural society in the 1930s and also a countryside shop from the 1950s.

[17] The exhibit Terra Mare at Köpmanholmen shows how post-glacial rebound has affected the coastal landscape.

The lively trafficked Seven Bridges' Road (De sju broarnas väg) goes through Larsmo and connects the municipality with the mainland.

The INGSVA (previously: Haldin & Rose) bus company has a number of lines going through the municipality.

The winter sports are concentrated to Holm where there are 5.5 km of skiing paths as well as facilities for biathlon.

There are nine un-supervised beaches in the municipality: Vikarholmen, Assarskär, Fagernäs, Kackur, Sonamo, Köpmanholmen, Annäsgrundet, Svennasminne and Brännbacka.