Slovincian became extinct in the early twentieth century ultimately due to stigmatization from Germans.

[12][10][11] However, individual words and expressions survived until after World War II, when the region became Polish.

This article will use a modified Kashubian orthography designed with northern dialects in mind used by some authors.

Additionally, breve ⟨˘⟩ is used for short vowels that appear in some loanwords, and macron ⟨¯⟩ is used to indicate length in one set of words.

Slovincian native vowels do not show any phonemic difference in length except in one set of words; however, loanwords show unpredictability as to whether the given vowel will be long or short, giving a series of long or short loan-phonemes, existing only in loanwords.

The pronouns tewa, jewa, czewa, njewa, etc., are subject to irregular phonetic reduction and can be realized with either ⟨ë⟩ or ⟨e⟩, with an ultimate underlying ⟨e⟩.

/ɵ/ can optionally be stressed in a few monosyllabic, common words, resulting from a reduction due to rapid speech and frequent use.

[48][49][50] ⟨a⟩ before nasal consonants and when stressed has an allophone ⟨ã⟩, and becomes [ã] again in the same position when unstressed as an alternative, non-phonemic pronunciation.

[63][21] Slovincian shares many similar developments as Kashubian, with some notable differences being: Long *a, often from being with a tautosyllabic voiced consonants, became usually and <ó> (via ) before nasals.

Slovincian grammar displays typical Slavic features, including declinable nouns, adjectives, verbs, pronouns, and numerals, as well as comparative and superlative forms, but notably retains a dual number.

The ancestors of the Slovincians, the West Slavic Pomeranians, moved in after the Migration Period.

The adoption of Lutheranism in the Duchy of Pomerania in 1534[74][75][76] distinguished the Slovincians from the Kashubes in Pomerelia, who remained Roman Catholic.

[13] In the 16th century, "Slovincian" was also applied to the Slavic speakers in the Bytów (Bütow) region further south.

[13] In the 16th and 17th century, Michael Brüggemann (also known as Pontanus or Michał Mostnik), Simon Krofey (Szimon Krofej), and J.M.

Krofey, pastor in Bytów (Bütow), published a religious song book in 1586, written in Polish but also containing some Kashubian words.

Brüggemann, pastor in Schmolsin, published a Polish translation of some works of Martin Luther and biblical texts, also containing Kashubian elements.

[13] In the 1950s, mainly in the village of Kluki (formerly Klucken), a few elderly people still remembered fragments of Slovincian.