On September 29, 1789, Congress officially created the U.S. Military. From the article:
"On this day in 1789, the final one of the congressional session, the lawmakers passed an act that morphed a small force inherited from the Continental Congress — one that had been created under the Articles of Confederation — into the U.S. Army.
Although the newly adopted U.S. Constitution charged Congress with raising and regulating the nation’s military forces, House and Senate members delayed action. Busy organizing the federal government and debating the location of the new capital, Congress neglected dealing with the issue until prodded to do so by President George Washington.
On Aug. 7, 1789, Washington reminded Congress the provisions for troops made under the Continental Congress needed to be superseded by action under the Constitution. It was an issue, Washington wrote the legislators, “of national importance and necessity of which I am deeply impressed.”
A lingering suspicion of standing armies also fueled Congress’ reluctance to act. It was widely believed that state militias could adequately deal with the nation’s defense needs. However, continued clashes with native tribes, in which the American side often fared badly, caused a shift in thinking that laid the foundation for a professional army.
Its first iteration was known as “The Legion of the United States,” which existed from 1792 to 1796 under the command of Maj. Gen. Anthony Wayne. In 1796, Wayne accepted the surrender of all British forts located illegally within the United States, in violation of the 1783 Treaty of Paris. The legion also raided the Native American stronghold of Kekionga. It built fortifications in the town and named it Fort Wayne, in honor of its commanding general. (Wayne died in Erie, Pennsylvania, on Dec. 15, 1796.)
Multiple fiascos during the War of 1812 persuaded the federal establishment to initiate a thorough reform of the War Department. John C. Calhoun, the secretary of war, reorganized the department into a system of bureaus, whose chiefs held office for life, with a commanding general in the field — although the Congress did not authorize this position.
Throughout the 1840s and 1850s, Winfield Scott served as the nation’s senior general, retiring at the start of the Civil War in 1861. The bureau chiefs acted as advisers to the secretary while commanding their own troops and field installations. Congress regulated the affairs of the bureaus."