About:Estonian is the official language of Estonia, spoken natively by about 1.1 million people in Estonia and tens of thousands in various migrant communities. It belongs to the Finnic branch of the Uralic language family. One distinctive feature that has caused a great amount of interest among linguists is what is traditionally seen as three degrees of phoneme length: short, long, and "overlong", such that /toto/, /toto/ and /toto/ are distinct. In actuality, the distinction is not purely in the phoneme length, and the underlying phonological mechanism is still disputed. The two different historical Estonian languages (sometimes considered dialects), the North and South Estonian languages, are based on the ancestors of modern Estonians' migration into the territory of Estonia in at least two different waves, both groups speaking considerably different Finnic vernaculars. Modern standard Estonian has evolved on the basis of the dialects of Northern Estonia. The domination of Estonia after the Northern Crusades, from the 13th century to 1918 by Denmark, Germany, Sweden, and Russia delayed indigenous literacy in Estonia. Estonian grammar published in Reval in 1637 by Heinrich Stah. The oldest written records of the Finnic languages of Estonia date from the 13th century. Originates Livoniae in Chronicle of Henry of Livonia contains Estonian place names, words and fragments of sentences.