In the 17th and 18th centuries it was the location of a graveyard. In 1812 Senate Square was designated as the main square for the new capital of Helsinki in the city plan designed by Johan Albrecht Ehrenström. The Palace of the Council of State (or Government Palace) was completed on the eastern side of the Senate Square in 1822. It served as the seat of the Senate of Finland until it was replaced by the Council of State in 1918, and now houses the offices of the Prime Minister of Finland and the cabinet.