The Northern Department was a department of the government of England and later the Kingdom of Great Britain, responsible for dealing with government business in the northern part of Europe. This included foreign affairs concerning such northern powers as Russia, Sweden, Denmark, the Netherlands and the Holy Roman Empire. It was administered by the Secretary of State for the Northern Department.
The Northern Department's opposite number within government was the Southern Department, responsible (as its name suggests) for affairs in southern Europe as well as domestic and colonial affairs.
In 1782, the Northern and Southern Departments were reorganized, with the Foreign Office taking over their foreign affairs responsibilities and Home Office taking over their domestic affairs responsibilities.