Today, there are approximately 6–7 million ethnic Finns and their descendants worldwide, with the majority of them living in their native Finland and the surrounding countries, namely Sweden, Russia and Norway.
An overseas Finnish diaspora has long been established in the countries of the Americas and Oceania, with the population of primarily immigrant background, namely Australia, Canada, New Zealand, Brazil, and the United States.
[43] The term "Finn" occasionally also has the meaning "a member of a people speaking Finnish or a Finnic language".
Such names as Fenni, Phinnoi, Finnum, and Skrithfinni / Scridefinnum appear in a few written texts starting from about two millennia ago in association with peoples located in a northern part of Europe, but the real meaning of these terms is debatable.
The Icelandic Eddas and Norse sagas (11th to 14th centuries), some of the oldest written sources probably originating from the closest proximity, use words like finnr and Finnas inconsistently.
Current research has disproved older hypotheses about connections with the names Häme (Finnish for 'Tavastia')[44] and Proto-Baltic *žeme / Slavic землꙗ (zemlja) meaning 'land'.
Petri Kallio had suggested that the name Suomi may bear even earlier Indo-European echoes with the original meaning of either "land" or "human",[46] but he has since disproved his hypothesis.
[47] As other Western Uralic and Baltic Finnic peoples, Finns originated between the Volga, Oka, and Kama rivers in what is now Russia.
The second wave of migration brought the main group of ancestors of Finns from the Baltic Sea to the southwest coast of Finland in the 8th century BC.
Furthermore, the traditional Finnish lexicon has a large number of words (about one-third) without a known etymology, hinting at the existence of a disappeared Paleo-European language; these include toponyms such as niemi, 'peninsula'.
Agriculture, along with the language, distinguishes Finns from the Sámi, who retained the hunter-gatherer lifestyle longer and moved to coastal fishing and reindeer herding.
Christianity spread to Finland from the Medieval times onward and original native traditions of Finnish paganism have become extinct.
[54] Swedish kings conquered western parts of Finland in the late 13th century, imposing Roman Catholicism.
Reformation in Sweden had the important effect that bishop Mikael Agricola, a student of Martin Luther's, introduced written Finnish, and literacy became common during the 18th century.
Although ostensibly based on late Iron Age settlement patterns, the heimos have been constructed according to dialect during the rise of nationalism in the 19th century.
The regions of Finland, another remnant of a past governing system, can be seen to reflect a further manifestation of a local identity.
An estimated 450,000 first- or second-generation immigrants from Finland live in Sweden, of which approximately half speak Finnish.
The majority moved from Finland to Sweden following the Second World War, contributing and taking advantage of the rapidly expanding Swedish economy.
There is also Meänkieli, a language developed in partial isolation from standard Finnish, spoken by three minorities, Tornedalians, Kvens and Lantalaiset, in the border area of northern Sweden.
The use of mitochondrial "mtDNA" (female lineage) and Y-chromosomal "Y-DNA" (male lineage) DNA-markers in tracing back the history of human populations has been gaining ground in ethnographic studies of Finnish people (e.g. the National Geographic Genographic Project[60] and the Suomi DNA-projekti.)
[67][61][68] They show relative affinity to Northern Russians as well,[69][67][70] who are known to be at least partially descended from Finno-Ugric-speakers who inhabited Northwestern Russia before the Slavs.
Finns being an outlier population has to do with their gene pool having reduced diversity[73] and differences in admixture, including Asian influence, compared to most Europeans.
[65]Finns share more identity-by-descent (IBD) segments with several other Uralic-speaking peoples, including groups like Estonians, the Sami and the geographically distant Komis and Nganasans, than with their Indo-European-speaking neighbours.
[65] Finns can be roughly divided into Western and Eastern (or Southwestern and Northeastern) Finnish sub-clusters, which in a fine-scale analysis contain more precise clusters that are consistent with traditional dialect areas.
[81][65] When looking at the fixation index (FST) values, the distance within Finns from different parts of the same country is exceptional in Europe.
[76] The division is related to the later settlement of Eastern Finland by a small number of Finns, who then experienced separate founder and bottleneck effects and genetic drift.
[85] Despite the differences, the IBS analysis points out that Western and Eastern Finns share overall a largely similar genetic foundation.
[83][86] In the 19th century, the Finnish researcher Matthias Castrén prevailed with the theory that "the original home of Finns" was in west-central Siberia.
[91] Genotype analyses across the greater European genetic landscape have provided some credibility to the theory of the Last Glacial Maximum refugia.