During the 14th century, Queen Margaret I of Denmark was battling Albert of Mecklenburg for Scandinavian supremacy. Albert had been King of Sweden since 1364 and Duke of Mecklenburg since 1383. The Vitalian Brotherhood were hired in 1392 by the Dukes of Mecklenburg to fight against Denmark, after Queen Margaret had imprisoned Albert and his son Eric of Mecklenburg in order to subdue the Kingdom of Sweden. While Queen Margaret's forces were besieging Stockholm, the blockade runners who came to be known as the Victual Brotherhood engaged in war at sea and shipped provisions to keep the city supplied. The name Victual Brothers is derived from the Latin word ""victualia"" — meaning provisions — and refers to their first mission, which was to supply the besieged city.