United States Department of War in the context of "United States Secretary of the Army"

Leslie Richard Groves Jr. (17 August 1896 – 13 July 1970) was a United States Army Corps of Engineers officer who oversaw the construction of the Pentagon and directed the Manhattan Project, a top secret research project that developed the atomic bomb during World War II.

The son of a U.S. Army chaplain, Groves lived at various Army posts during his childhood. In 1918, he graduated fourth in his class at the United States Military Academy at West Point and was commissioned into the United States Army Corps of Engineers. In 1929, he went to Nicaragua as part of an expedition to conduct a survey for the Inter-Oceanic Nicaragua Canal. Following the 1931 Nicaraguan earthquake, Groves took over Managua's water supply system, for which he was awarded the Nicaraguan Presidential Medal of Merit. He attended the Command and General Staff School at Fort Leavenworth, Kansas, in 1935 and 1936, and the Army War College in 1938 and 1939, after which he was posted to the War Department General Staff. Groves developed "a reputation as a doer, a driver, and a stickler for duty". In 1940 he became special assistant for construction to the Quartermaster General, tasked with inspecting construction sites and checking on their progress. In August 1941, he was appointed to create the gigantic office complex for the War Department's 40,000 staff that would ultimately become the Pentagon.

The Department of the Army (DA) is one of the three military departments within the United States Department of Defense. The DA is the federal government agency within which the United States Army (U.S.) is organized. It is led by the secretary of the Army, a civilian official appointed by the president and confirmed by the Senate. The highest-ranking military officer in the department is the chief of staff of the Army, who is also a member of the Joint Chiefs of Staff. Other senior officials of the department are the under secretary of the Army (principal deputy to the secretary) and the vice chief of staff of the Army (principal deputy to the chief of staff.)

The DA is a successor to the Department of War which was originally formed in 1789 as an Executive Department of the United States. The Department of War was split by the National Security Act of 1947 into the Department of the Army and Department of the Air Force on September 18, 1947.

Louisiana was a dominant population center in the southwest of the Confederate States of America, controlling the wealthy trade center of New Orleans, and contributing the French Creole and Cajun populations to the demographic composition of a predominantly Anglo-American country. In the antebellum period, Louisiana was a slave state, where enslaved African Americans had comprised the majority of the population during the eighteenth-century French and Spanish dominations. By the time the United States acquired the territory (1803) and Louisiana became a state (1812), the institution of slavery was entrenched. By 1860, 47% of the state's population were enslaved, though the state also had one of the largest free black populations in the United States. Much of the white population, particularly in the cities, supported slavery, while pockets of support for the U.S. and its government existed in the more rural areas.

Louisiana declared that it had seceded from the Union on January 26, 1861. Civil-War era New Orleans, the largest city in the South, was strategically important as a port city due to its southernmost location on the Mississippi River and its access to the Gulf of Mexico. The U.S. War Department early on planned for its capture. The city was taken by U.S. Army forces on April 25, 1862. Because a large part of the population had Union sympathies (or compatible commercial interests), the U.S. government took the unusual step of designating the areas of Louisiana then under U.S. control as a state within the Union, with its own elected representatives to the U.S. Congress. For the latter part of the war, both the U.S. and the Confederacy recognized their own distinct Louisiana governors. Similarly, New Orleans and 13 named parishes of the state were exempted from the Emancipation Proclamation, which applied exclusively to states in rebellion against the Union.

The National Security Act of 1947 (Pub.L. 80-253, 61 Stat. 495, enacted July 26, 1947) was a law enacting major restructuring of the United States government's military and intelligence agencies following World War II. The majority of the provisions of the act took effect on September 18, 1947, the day after the Senate confirmed James Forrestal as the first secretary of defense.

The act merged the Department of the Army (renamed from the Department of War), the Department of the Navy, and the newly established Department of the Air Force (DAF) into the National Military Establishment (NME). The act also created the position of the secretary of defense as the head of the NME. It established the United States Air Force under the DAF, which worked to separate the Army Air Forces into its own service. It also protected the Marine Corps as an independent service under the Department of the Navy. Aside from the unification of the three military departments, the act established the National Security Council and the Central Intelligence Agency, the latter of which is headed by the director of central intelligence.

The secretary of war was a member of the U.S. Cabinet, beginning with George Washington's administration. A similar position, called either "Secretary at War" or "Secretary of War", had been appointed to serve the Congress of the Confederation under the Articles of Confederation between 1781 and 1789. Benjamin Lincoln and later Henry Knox held the position. When Washington was inaugurated as the first president under the Constitution, he appointed Knox to continue serving as secretary of war.

The secretary of war was the head of the War Department. At first, he was responsible for the United States Army and the Navy. In 1798, the secretary of the Navy was created by statute, and the scope of responsibility for the War Department was reduced to the Army. From 1886 onward, the secretary of war was in the line of succession to the presidency, after the vice president of the United States, the Speaker of the House of Representatives, the president pro tempore of the Senate and the secretary of state.

In the United States, a national monument is a protected area that can be created from any land owned or controlled by the federal government by proclamation of the president of the United States or an act of Congress. National monuments protect a wide variety of natural and historic resources, including sites of geologic, marine, archaeological, and cultural importance. The Antiquities Act of 1906 gives presidents the power to proclaim national monuments by executive action. In contrast, national parks in the U.S. must be created by Congressional legislation. Some national monuments were first created by presidential action and later designated as national parks by congressional approval.

The 138 national monuments are managed by several federal agencies: the National Park Service, United States Forest Service, United States Fish and Wildlife Service, the Bureau of Land Management, and the National Oceanic and Atmospheric Administration (in the case of marine national monuments). Historically, some national monuments were managed by the War Department.

The Marias Massacre (also known as the Baker Massacre or the Piegan Massacre) was a massacre of Piegan Blackfeet Native peoples committed by United States Army forces under Major Eugene Mortimer Baker as part of the Indian Wars. The massacre occurred on January 23, 1870, in Montana Territory. Approximately 200 Native people were killed, most of whom were women, children, and older men.

As part of a campaign to suppress Mountain Chief's band of Piegan Blackfeet, the U.S. Army attacked a different band led by Chief Heavy Runner, to whom the United States government had previously promised their protection. This resulted in public outrage and a long-term shift towards a "Peace Policy" by the Federal Government, as advocated by President Ulysses S. Grant. Grant kept the Bureau of Indian Affairs as a division of the Department of the Interior although the War Department was trying to regain control. He then appointed men recommended by various religious clergy—including Quakers and Methodists—as Indian agents, in hopes that they would be free of the corruption he had previously found in the department.