Roslagen is the name of the coastal areas of Uppland province in Sweden, which also constitutes the northern part of the Stockholm archipelago. Historically, it was the name for all the coastal areas of the Baltic Sea, including the eastern parts of lake Mälaren, belonging to Svealand. The name was first mentioned in the year 1493 as "Rodzlagen". Before that the area has been known as Roden, which is the coastal equivalent to inland Hundreds. When the king would issue a call to leidang, the Viking Age equivalent of military conscript service, a Roden district was responsible for raising a number of ships for the leidang navy.