In 1789 Congress created three Executive Departments: Foreign Affairs (later in the same year renamed State), Treasury, and War. It also provided for an Attorney General and a Postmaster General. Domestic matters were apportioned by Congress among these departments.
The idea of setting up a separate department to handle domestic matters was put forward on numerous occasions. It wasn't until March 3, 1849, the last day of the 30th Congress, that a bill was passed to create the Department of the Interior to take charge of the Nation's internal affairs:The Interior Department had a wide range of responsibilities entrusted to it: the construction of the national capital's water system, the colonization of freed slaves in Haiti, exploration of western wilderness, oversight of the District of Columbia jail, regulation of territorial governments, management of hospitals and universities, management of public parks,and the basic responsibilities for Indians, public lands, patents, and pensions. In one way or another all of these had to do with the internal development of the Nation or the welfare of its people.