The earliest known mention of Estonian migration to Finland comes from the 14th century, when it was mentioned that people had fled from the
Bishopric of Ösel–Wiek to the towns of
Turku and
Viipuri or their surroundings. Place names containing the elements
Est- and
Viro- are found across the southern coast of Finland, the former in traditionally Swedish-speaking and the latter in Finnish-speaking areas. One of the earliest attested examples of such names is
Virolahti, which was first mentioned in 1336 as
Viirlax. These names may refer to contacts between the locals and Estonians, or even to Estonian settlement, though the latter is less likely. Some later names may be references to migrants from
Swedish Estonia and
Livonia, who were not necessarily ethnic Estonians, and may have included
Estonian Swedes,
Livonians and
Latvians as well. Immigration from Estonia to Finland was low before 1990. After the collapse of the
Soviet Union and Estonia's accession to the
EU in 2004, emigration from Estonia to Finland increased rapidly. The migration of Estonians peaked in 2012, when more than 6,000 Estonians emigrated to Finland. In 2017, however, net migration from Estonia was negative, as Estonians returned to their country. The reasons for this are rising salaries in Estonia and family ties. Nevertheless, the Estonian population is still growing, although at a much slower rate than before. == Population by municipalities ==