Simplify the following text for a Grade 13 native English-speaking person.
Original: It is situated at the entrance to the Gulf of Bothnia and forms an autonomous , demilitarized , monolingually Swedish-speaking administrative province , region and historical province of Finland .
Simplified: They are situated at the entrance to the Gulf of Bothnia and form an autonomous , demilitarised , monolingually Swedish-speaking region of Finland .