The Finnish language is a Finnic language spoken mostly in Finland that descends from Proto-Finnic and in turn from Proto-Uralic. It is closely related to the Estonian language as well as less-spoken languages, such as Karelian and Veps, and is also distantly related to Hungarian.

The history of the Finnish language can be divided into multiple eras. The earliest phase, Early Finnish (), lasted from its separation from the other Finnic languages sometime around the end of the first millennium AD until 1540. Around this time, the first Finnish texts of note that survive were written, marking the start of the Old Literary Finnish () period. This lasted until the early 19th century, when some time around 1810–1820, the development of the Finnish language entered a new phase called Early Modern Finnish (). This developed into Modern Finnish () around the 1870s, by 1880 at the latest.

Origins

Finnish belongs to the Uralic language family and more specifically to the Finnic branch of this family. Thus, Finnish has developed from Proto-Finnic, which in turn has developed from Proto-Uralic. Neither Proto-Uralic nor Proto-Finnic was written down, and what is known of them has been derived through historical linguistics. This includes reconstructions, which are traditionally marked with an asterisk (*).

Finnish is noted for its conservatism. Many of the features reconstructed to Proto-Uralic, such as an agglutinating morphology, vowel harmony, consonant gradation, invariably initial (primary) stress, and possessive suffixes, are still present in Finnish today. Among the Finnic features that are not found in the other Uralic languages are adjective–noun agreement, the analytic perfect and pluperfect tenses, and possibly the default word order being SVO instead of SOV, although the Finnic word order was likely flexible, as in Finnish today.

Proto-Uralic was originally spoken east of the Ural Mountains, but after its dispersal not long before the 2nd millennium BC, Uralic languages had reached as far west as the upper reaches of the rivers Volga and Oka.: "The Uralic spread took place rapidly (...) The I-I contact episode gives a reliable absolute date for the Uralic divergence and dispersal: not long before 4000 BP." (...) "the western frontier of the Uralic family (...) lay along the upper Volga and Oka." Slightly after the beginning of the spread of Sámi languages (to southeastern Finland by around 1000 BC and to Central Scandinavia by 200 AD), the Finnic speakers then began to spread along the upper Oka,: "Saamic moved (...) reaching southeastern Finland c. 3000 BP, and some time after that spread to central Scandinavia perhaps as early as 200 CE, (...) Finnic spread separately, starting slightly later. Moving along waterways of what Lang 2018:310 terms the Southwest Passage (middle-upper Oka to the south coast of the Gulf of Finland) (...) it took ancestral Pre-Finnic speakers over half a millennium to reach the Baltic coast." and the main group reached the northern and western coasts of Estonia around 800 BC. Shortly thereafter, they also reached southwestern and southern Finland. Development of Proto-Finnic into Late Proto-Finnic took place in Northern Estonia and spread across the gulf into southwestern and southern Finland in the Roman Iron Age, marking a second arrival into Finland. The speakers of the earlier Finnic varieties as well as the Sámi-speaking populations that had already settled the same area shifted their language to Late Proto-Finnic. Subsequently, Late Proto-Finnic continued its expansion north of the Gulf of Finland, along the Kokemäenjoki river valley, reaching Tavastia and then east to Karelia by the 8th century AD and Savonia between the 8th and 11th centuries AD. Upon reaching Karelia, Finnic unity began to break down. As they spread, the Finnic speakers assimilated the Sámi-speaking populations living inland, eventually leaving the Sámi languages in what was once their northwestern periphery.

The breakup of the Finnic languages can also be studied linguistically. After South Estonian and Livonian branched off, the remaining core of the Finnic languages then split into Northern Finnic (including Finnish) and Central Finnic (including Estonian). Western Finnish (the western dialects of Finnish) represents a separate node in the tree under Northern Finnic. Eastern Finnish (the eastern dialects), also under Northern Finnic, is more closely related to Karelian and Ingrian; they share a common proto-language, known in literature as Proto-Karelian (). Therefore, Finnish has effectively developed from two different (albeit closely related) languages melding into one.

Among the sound and grammatical changes that can be noted from Late Proto-Finnic to North Proto-Finnic are (with Finnish reflexes): *kt, *pt > *ht (*koktu > ) the third-person singular verb ending *-pi (*anta-pi > dialectal , modern standard ) *kc > *ks, *pc > *ps (*kakci > , *lapci > ) *ck > *tk (*pucki > ) *c > *s (*cika > , *keüci > ), except in *cc, *cr sporadic *ai > *ei (*haina > , *raici > ) *ë (e.g. Estonian õ) > *e (*tërva > , *lainëh > ) development of *ö in non-initial syllables under vowel harmony (*näko > ).

Estimates put the number of Finnish words inherited from Proto-Uralic at around 300–400; despite their small number, they make up approximately 70–80 percent of average speech. Inherited words include nouns related to relatives, body parts, animals, and plants, along with many basic verbs and most of the pronouns.

Loanwords

The oldest loanwords in Finnish were already present in Proto-Uralic, which borrowed words from Indo-Iranian languages. Proto-Finnic has many loanwords from the Baltic (over 250 words), Germanic (over 500) and Slavic languages (perhaps over 100). After Proto-Finnic, Finnish has borrowed extensively from Swedish, accounting for about a half of all loanwords in the language. Furthermore, many words were also borrowed from Middle Low German, even without Swedish mediation. More recently, English has become the most important source of new loanwords, as it has in the rest of the Western world.

Loanwords in Finnish, both old and new, include:

+ Some examples of loanwords in Finnish (large table) Finnish Source Comparandum "value" Indo-Iranian Ossetian arǧ "god" Sanskrit dyumát "spindle" Sanskrit cāttra "slave" Sanskrit ā́rya "cultured buttermilk" Avestan paēman "hundred" Sanskrit śatá "hammer" Sanskrit vájra "tooth" Baltic Lithuanian "tribe" Lithuanian "all" Lithuanian "neck" Latvian "salmon" Latvian "bride" Lithuanian "sister" Lithuanian "dear" Germanic Old Norse "and" Gothic jah "people" Gothic hansa "king" Old English "bread" Old Norse "hoop, ring" Old Norse "power, might" Icelandic "mother" Gothic aiþei "occupation, profession" Middle Low GermanHäkkinen, Kaisa. Chronological stratification of the vocabulary of Finnish (2010) "wedding" Middle Low German "church" Middle Low German "honest" Middle Low German "madam, lady" Middle Low German "trousers" Swedish "coffee" Swedish "law" Swedish "soul" Swedish "chair" Swedish "pillow" Swedish "to consecrate" Swedish "spoon" Old East Slavic lŭžĭka "cross" Old East Slavic krĭstŭ "goods, ware" Russian tovar

In a 2018 article, linguist estimated that out of the vocabulary present in a learner's dictionary, 49 percent of words were native, 46 percent were loanwords, and the remaining five percent had a disputed etymology. Out of the native vocabulary, 45 percent were older than Proto-Finnic, 52 percent were from the Proto-Finnic era, and the remaining 3 percent from after Proto-Finnic.

Early Finnish

Early Finnish represents the earliest period of the Finnish language as separate from the other Finnic languages. Its start date is placed around 700 AD. Some sources distinguish between Early and Medieval Finnish, with a crossover point around 1200. By 1000 AD, there were four well-defined dialect regions: Southwest Finland, Tavastia, Karelia and Savonia. These belonged to two diachronically distinct language groups of Western and Eastern Finnish. Southwest Finland and Tavastia belonged to Western Finnish, while Savonia and Karelia belonged to Eastern Finnish. Early (and Medieval) Finnish covers the western dialects, while the eastern dialects instead developed as part of Proto-Karelian during this time.

For reference, today, there are seven dialectal groups: the Southwest Finnish dialects, the Tavastian dialects, the South Ostrobothnian dialect, the Central and North Ostrobothnian dialects, the Peräpohjola dialects, the Savonian dialects, and the South Karelian dialects; the first five comprise the western dialects, and the last two the eastern dialects. The South Ostrobothnian dialect likely developed between the 9th and 12th centuries. The more northern dialects (the Central and North Ostrobothnian dialects and the Peräpohjola dialects) tend to display a mix of western and eastern features due to Karelian influence.Paunonen, Heikki. Suomen murteiden ryhmittelystä ja niiden suhteesta viron murteisiin (2023). p. 221

Written attestations of Early Finnish are scant, mostly consisting of individual names of both people and locations since at least the 13th century. Even such fragmentary records are useful to understand the history of Early Finnish and can be used to help establish approximate dates for certain sound changes.

Among the sound changes that can be noted during the Early Finnish period (including Medieval Finnish) are: the spirantization of *b > *ꞵ (> v), *d > *ẟ (), *g > *ɣ likewise, in consonant clusters before voiced consonants, *k > *ɣ, *p > *ꞵ (> v), *t > *ẟ () *cc > *θθ *cr > *θr > *hr the diphthongization of *ee > *ie, *oo > *uo, *öö > *üö semi-long consonants merging with short consonants (e.g. *k' > *k)

Heikkilä (2016) lists more changes, some of which were regional: loss of word-final *-k and their corresponding intervocalic *ɣ (seemingly early) vocalization of (original) *k, *p, *t in clusters before voiced consonants *eü > *öü, *iü > *üü (in initial syllables) *lẟ > *ll, *nẟ > *nn, *rẟ > *rr *mꞵ > *mm elision of intervocalic *h between unstressed syllables

Apocope, at least in certain inflected forms, likely began around the 14th century and rapidly gained ground in the 15th century. Western Finnish dialects began to be clearly distinct in the Late Middle Ages, but nevertheless remained relatively uniform due to high mobility until the 16th century.

Proto-Karelian, which yielded the Eastern Finnish dialects, is thought to have undergone the elision of intervocalic *-d-, *-g-, the development of the plural marker *-loi-, and the labialization of *e in non-initial syllables when followed by labial consonants. Diphthongization of *ee, *oo, *öö had not yet occurred in Proto-Karelian, and instead spread from the western dialects to Eastern Finnish and to Karelian through the Savonian dialects after the breakup of Proto-Karelian.

The earliest known full sentence in Finnish is dated to around 1450 and appears in a travel journal primarily written in German: . These words are ascribed to the Bishop of Turku at the time. During Swedish rule in Finland (starting from the 1150s), Swedish was the language of administration, while Latin was used in the church (until the Reformation); Finnish was merely the language of the common people. However, the Bishopric of Turku was using Finnish in church service already since 1492, when it was decreed that at least the Lord's Prayer, Hail Mary and the creed had to be written down and read to the people in their own language. None such texts have survived.

Old Literary Finnish

Mikael Agricola