In historical times, Kalix was the name of the court district (Swedish: domsaga) Kalix Lower Court District. It covered two parishes: Lower and Upper Kalix (Swedish: Nederkalix and Överkalix, respectively). The chalice on the coat of arms was present in the Nederkalix coat of arms in 1800, and was incorporated into that of Kalix Municipality in 1989. The choice of symbol originates from the similarity between the Latin root of chalice, calix, and the local sami pronunciation of Gáláseatnu, an ancient name for the Kalix river.
The extent of the Kalix Municipality is based on the traditional extent of the Kalix Language, although slight dialectal differences can be found from Sangis in the east, Töre in the west and Övermorjärv in the north. Today it is spoken along with Sami, Finnish, Meänkieli, Upper Kalix Language, and the national standard language Swedish, which has replaced the Kalix Language as common language in every day life. Like other North Germanic languages the Kalix Language origins from Old Norse and Proto-Norse, spoken by immigrating Germanic settlers during the Viking Age.