Latgalian is an Eastern Baltic language, although it is sometimes considered a dialect of Latvian. The Latvian language law classifies it as a "historical form of Latvian". It is mostly spoken in Latgale, the eastern part of Latvia. The 2011 Latvian census established that 8.8% of Latvia's inhabitants, or 164,500 people, speak Latgalian daily. 97,600 of them live in Latgale, 29,400 in Riga and 14,400 in the Riga Planning Region.

Latvian, also known as Lettish, is an East Baltic language belonging to the Indo-European language family. It belongs to the Baltic subbranch of the Balto-Slavic branch of the family and it is spoken in the Baltic region. It is the language of Latvians and the official language of Latvia as well as one of the official languages of the European Union. There are about 1.2 million native Latvian speakers in Latvia and 100,000 abroad. Altogether, 2 million, or 80% of the population of Latvia, spoke Latvian in the 2000s, before the total number of inhabitants of Latvia slipped to 1.8 million in 2022. Of those, around 1.16 million or 62% of Latvia's population used it as their primary language at home, though excluding the Latgale and Riga regions it is spoken as a native language in villages and towns by over 90% of the population.