With a 2020 population of 27,386 distributed over 10.55 square miles (27.33 km2), Karlskoga is the second-largest city in both Örebro County and the historical province of Värmland.

[6] The broader Karlskoga area distinguishes itself from its surrounding regions, e.g. the Närke Plain, with its abundant woodlands and hills, which made it better suited for activities beyond agriculture, such as the ironwork industry.

Today, Karlskoga is still a thriving center of the arms industry, but its economy is more diverse than during the peak-Bofors era.

Ethnic Swedes (people from the historical provinces of Närke and Södermanland), and particularly Finns,[a] began to settle the area,[12][13] where they took up the farming method slash-and-burn.

They were followed by Huguenots, fleeing religious oppression in France,[14] and by other groups including both Dutch and German settlers, mostly skilled metalsmiths.

It was small in size, and was solely made up of the sacristy still preserved at this site,[15] which was a consequence of population increase in the years prior.

[23][24] Because of that it was here his famous testament that was written in Paris in 1895 was legally registered, which eventually made it possible to establish the Nobel Prize.

[25][26] During the first decade of the 21st century, approximately 1,000 apartments in multi-family buildings were demolished due to reduced demand for firearms products.

[28] Karlskoga is situated more or less in a low mountainous ridge called Kilsbergen that separates Närke from Värmland.

[29] The city borders on the municipalities of Hällefors and Storfors to the north; Lekeberg to the east; Degerfors and the Lake Möckeln to the south; and Kristinehamn to the west.

The Rosendal neighbourhood, historically significant for the architecture of its homes,[30] planned community by the Bofors Works, was designated as an area of national interest for cultural heritage.

[31] Karlskoga's population grew steadily from the time when arms manufacturer Bofors had started to expand, until the 1970s.

The city is an important center for the arms manufacturing and pharmaceutical industries; it is home to various multinational corporations, including subsidiaries and divisions of Bharat Forge, BAE Systems, Saab AB (SAAB Bofors Dynamics), Nammo, Cambrex Corporation, Recipharm, Moelven Industrier,[42] and Eurenco.

[43] Karlskoga has a connection with notable literary figures, including Maja Ekelöf, whose best-selling Rapport från en skurhink was published in 1970.

[44][45] Nobel laureate Selma Lagerlöf stayed in Karlskoga during her confirmation period with Tullius Hammagren.

Karlskoga is home to several stadiums, of which Nobelhallen is the largest (it hosted the 1979 World Junior Ice Hockey Championships).

Notable Olympic champions include Ulrika Knape in diving, as well as Agneta Andersson[50] and Maria Haglund in canoeing.