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Executive departments of the U. S. Government existed before 1789. The Continental Congress at first transacted all executive business through committees; then through commissions composed partly of its own members, partly of others. In 1776 the Treasury Office of Accounts was established, and a comptroller, auditor and treasurer were added two years later. In 1781 four executive departments were organized, under a Superintendent of Finance and Secretaries of War, Marine and Foreign Affairs, respectively. A Postmaster-General had been provided in 1775. In 1784 the Treasury Department was put in the charge of a board of three, but otherwise the system continued until the inauguration of the new government in 1789. In that year Congress provided for Departments of State, the Treasury and War, and instituted the office of Attorney-General. The first plan contemplated separate departments of foreign affairs and home affairs, but finally these were united in the Department of State. The Navy Department was established in 1798, the Interior Department in 1849, the Department of Justice in 1870, the Department of Agriculture in 1889. For details of their history, see articles under their individual names.