Åland's Regional Assembly convened for its first plenary session in Mariehamn, Åland; today, the day is celebrated as Self-Government Day of Åland.

Åland is an autonomous and demilitarised region of Finland. Receiving its autonomy by a 1920 decision of the League of Nations, it is the smallest region of Finland by both area and population (30,654), constituting 0.51% of Finland's land area and 0.54% of its population. Its only official language is Swedish and the capital city is Mariehamn.

Mariehamn is the capital of Åland, an autonomous territory under Finnish sovereignty. Mariehamn is the seat of the Government and Parliament of Åland, and 40% of the population of Åland live in the city. It is mostly surrounded by Jomala, the second-largest municipality in Åland in terms of population; to the east, it is bordered by Lemland. Like the rest of Åland, Mariehamn is unilingually Swedish-speaking and around 81% of the inhabitants speak it as their native language.

June 9 is the 160th day of the year in the Gregorian calendar; 205 days remain until the end of the year.

Åland's Autonomy Day, or Åland's Self-Government Day, is celebrated annually on 9 June to commemorate the first meeting of the Åland County Council on that date in 1922. Åland's self-government from Finland was established in 1921 by a decision of the League of Nations, following the Åland Movement's demand for reunification with Sweden.