A Brief History of the United States Army

History of the Army

The United States Army wasn’t always the military superpower it is today. As the oldest branch of the U.S. Armed Forces, the Army can trace its roots back to the Revolutionary War.

With each subsequent war and conflict, the Army has adapted and evolved to ensure it could continue to protect U.S. citizens and its allies.

Let’s look at the humble beginnings of the U.S. Army to see how it became the elite fighting force it is today.

The Origins of the U.S. Army

The Continental Army, a predecessor to today’s modern Army, was created by the Continental Congress on June 14, 1775, for the specific purpose of fighting against Great Britain in the war for independence. George Washington was named as commander of the young fighting force and many men who served in the British Army were officers in the Continental Army.

At first, the U.S. Army fought in the “British style.” However, as the war progressed, U.S. Army officers were influenced by military strategies and tactics introduced by the French, the Dutch, Indian tribes, and the Prussians.

These new strategies helped the Continental Army win decisive battles and eventually claim victory over the larger, stronger British military.

After the war, the Continental Army was quickly disbanded. Congress debated the merits of establishing of a standing militia controlled by the federal government in peacetime. Ultimately, it was rejected by Congress because they were wary of concentrating so much power in the hands of the President. The Militia Act of 1792 was passed in part to limit the size of any federally controlled Army.

However, George Washington was able to convince Congress to allow for a small standing army to defend against Native American populations on the western frontier. In addition, several states kept their own militias.

The War of 1812

History of the Army

It was during the War of 1812 when it became clear that the United States was ill-prepared for modern warfare.

At the height of the war, the Army had 60,000 enlisted men under federal command. There were another 400,000 members of various state militias that were called in as needed. However, this combined force struggled against the British and suffered massive casualties.

Despite these losses, the United States fended off the British for a second time and emerged from the War of 1812 still intact. After the conflict, America’s peacetime standing Army was reduced to just 9,000 enlisted men.

The Mexican-American War

The Mexican-American War in 1846 is important in the history of the Unites States Army because for the first time, the country relied mostly on a single federally-controlled fighting force with little support from state militias. 

The Army was approximately 90,000 soldiers strong during the conflict. Under the leadership of notable military leaders like General Winfield Scott, Stonewall Jackson, Ulysses S. Grant, and George McClellan, the Army scored decisive victories throughout the campaign.

After the War, the size of the Army was once again reduced to 10,000 men and focused on quelling conflicts with Native American tribes in newly settled lands.

The Civil War

History of the Army

On December 20, 1860, South Carolina seceded from the Union and the Civil War began.

During this war, the United States Army underwent its largest expansion to date. The number of enlisted men exploded from approximately 16,000 soldiers at the start of the war, to 1 million soldiers by 1865.

One reason for the large increase was the dismissal of the militia concept entirely during this time. Therefore, many militia men volunteered for the Army proper.

In addition, the draft was enacted midway through the war due to massive casualties. Finally, the enlistment of African American soldiers became legal in 1862. By the end of the war, the U.S. Army included 180,000 African American soldiers.

At the conclusion of the Civil War, Congress passed the Army Reorganization Act of 1866, which established a full-time Army under the command of the President. For the first time, American would have a full-fledged Army during peacetime.

However, low pay and poor conditions kept enrollment low. In 1899, Secretary of War Elihu Root made it his mission to fix these problems and create a modern fighting force.

World War I

History of the Army

When the U.S. became involved in the first world war, the Army was better prepared to fight than any other time in U.S. history.

The readiness of the Army was due to four main reasons:

1. The repeal of the Militia Act of 1792, which had prevented the government from establishing a major centralized fighting force up until this point.

2. Experienced military leaders.

3. The establishment of National Guard and the Army Reserves.

4. An existing staff for general organization and administration duties.

During World War I, the Army grew to approximately 3.7 million troops in just 18 months. It’s estimated that 75% of those troops came to the Army though the Selective Service Act of May 1917, also known as the draft.

The speed and efficiency of this military expansion was a major factor in the decisive victory achieved by the Allies in November 1918. It was also clear evidence that the innovations put in place by Elihu Root less than two decades prior were effective.

After the war was over, however, the Army reduced its numbers to 125,000 active troops. Those numbers remained steady through 1939.

World War II

History of the Army

After Germany invaded France in May 1940, the U.S. government started the draft again, which raised the Army’s numbers to 1.64 million troops by the time the United States entered the war in December of 1941.

The Army continued to expand during World War II, reaching a total of 8.3 million troops. Those troops saw action in Europe, Asia, North Africa, Italy, and other regions around the globe.

World War II also saw for the first time, women playing a significant role in the Army. Approximately 150,000 women served as nurses, builders, mechanics, intelligence analysts, clerks, and administrators.

Many of these women returned to civilian life after the war ended, but the Women’s Army Corp (WAC) remained as separate unit within the U.S. Army until 1978. That year, the WAC was abolished, and women were integrated into all non-combat roles within the Army. It wouldn’t be until 2013 that those restrictions were lifted, and they were able to join their male counterparts in combat.

It was also during this time that Army chief of staff General George C. Marshall oversaw the reorganization of the Army into the Army Ground Forces, the Army Service Forces, and the Army Air Forces.

The Army Air Forces would later evolve into its own separate branch of the United States military thanks to the National Security Act of 1947: the Air Force.

After the United States defeated the Japanese to finally end the war, the Army once again reduced its numbers dramatically. The Army went from 8 million troops in 1945 to 550,000 troops in 1948.

The Korean War and the Cold War

History of the Army

The start of the United States’ involvement of the Korean War caused yet another expansion of the Army to about 1.5 million troops. It was also during this war that the Army was desegrated and African American troops were able to fight alongside white troops.

The end of the Korean conflict marked the first time that the Army maintained strong numbers during peacetime. Army leadership argued that sustained manpower was necessary because of the Cold War. It was believed that the U.S. must be prepared to assist western European allies should the Soviet Union decide to invade its neighbors.

While Congress believed that the Soviet Union was a threat, they also believed that the country’s air and naval powers, not ground forces, would play a more vital role in any conflict that might arise. Therefore, funding was diverted away from the Army to the Navy and Air Force in the 1950s.

Ironically, the proliferation of nuclear weapons during the 1960s and 1970s along with the new concept of “mutually assured destruction” led Congress to increase Army funding and support. It was believed that small ground battles would be far more likely to occur than full-on nuclear war.

The Vietnam War

History of the Army

Army training was reorganized to focus on mobilizing quickly, striking hard, and being able to deploy anywhere in the world. At the height of the Vietnam War, the U.S. Army had 1.4 million soldiers and saw a major upgrade in weaponry, vehicles, and equipment.

The U.S. armed forces officially withdrew from Vietnam in 1973. At the conclusion of the war the draft was officially ended, and the U.S. military has had an all-volunteer force since then. 

The U.S. Army in the 21st Century

The U.S. Army has been called upon heavily throughout the 21st Century as the attacks of September 11 on U.S. soil led to prolonged campaigns against Saddam Hussein in Iraq and al-Qaeda and the Taliban in Afghanistan.

Not only did the Army lead combat missions, but they also engaged in “nation-building” activities in Iraq and Afghanistan such as securing elections, creating safe zones around crucial locations, and training new military forces in those countries.

American combat missions in those countries have officially ended in the summer of 2021 after two decades of nearly continuous fighting.

The U.S. Army Today

The United States Army started as the humble Continental Army, put in place to literally help birth this nation. Today, it’s the is the most senior and the largest branch of the U.S. Armed Forces with 481,254 highly trained and brave soldiers. See how that compares to other branches of the military.

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History of the Army

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Dr. Phillip Gold is President/CEO of Empire Resume and has vast experience writing resumes for both professionals and servicemembers transitioning from the military into civilian roles. He served as a Captain in the U.S. Air Force and was responsible for leading nuclear missile security. Phillip is a Certified Professional Resume Writer and holds a BA in Communications from The Ohio State University, an MS in Instructional Technology, an MBA in Finance, and a PhD in Finance. 

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