From neutrality to victory: America's influence on WWI
Read about America’s involvement in World War One, including its key battles and how US participation helped to secure an Allied victory.
Image: Men of the 18th Machine Gun Battalion passing through St. Baussant in advance upon St. Mihiel on 13th September 1918 | Public Domain
The Great War is a cinematic documentary covering America’s involvement in World War I during the critical year of 1918. It follows General John J. Pershing, leader of the American Expeditionary Force, who is charged with training and deploying an army almost from scratch.
The show starts Sunday, 3rd November at 9pm on Sky HISTORY.
Between 1914 and 1918, World War I cost the lives of 8.5 million soldiers across both sides. This included nearly 177,000 US troops, making WWI the third deadliest war the country has fought. Here, we explore the extent of US involvement in The Great War and look at how the country’s participation helped to secure victory for the Allies.
The build-up to WWI
When the Austro-Hungarian Empire declared war on Serbia on 28th July 1914, it marked the official start of WWI. The build-up to this declaration had involved complex factors and tensions, including the rise of Serbian nationalism.
The precipitating event which led to WWI was the assassination of Archduke Franz Ferdinand by Serbian nationalist Gavrilo Princip one month earlier. Ferdinand was the heir to the Austro-Hungarian Empire and his killing was used as the justification for Austria-Hungary to act to quell Serbian nationalism.
Austria-Hungary’s declaration of war quickly triggered other countries to follow suit. This included Russia and Italy declaring war on Austria-Hungary, and Germany invading Luxembourg and Belgium. Meanwhile, Great Britain and France declared war on Germany.
These actions resulted in two warring sides. The Central Powers included Austria-Hungary, Germany, and the Ottoman Empire. The Allied Powers comprised Great Britain, France, Italy, Russia and – in time – the United States.
How did the US become involved in WWI?
America officially entered WWI on 6th April 1917, following a request to Congress by the 28th US President Woodrow Wilson.
Prior to this, Wilson had made several offers to broker peace between the Central Powers and the Allies. Both sides rejected these efforts and the conflict dragged on, with mounting casualties on both sides.
Wilson, a progressive Democrat, was initially committed to a US policy of neutrality. This was despite internal pressure from interventionists, particularly former US President Theodore Roosevelt (1901-1909). Wilson’s policy also stood firm amid acts of provocation by Germany.
In response to a blockade by the British Royal Navy, Germany launched a submarine campaign (known as unrestricted submarine warfare), which led to the sinking of three American ships in early 1915.
Then in May of the same year, 128 American citizens were among the 1,198 dead when the RMS Lusitania, a British ocean liner, was torpedoed by a German submarine (U-boat). The following year, four Americans were among those killed when the SS Sussex was also torpedoed.
The acts, particularly the sinking of the Lusitania, led Wilson to build up the US army and navy, in what was known as a 'preparedness movement'. The passing of the National Defense Act of 1916 and Naval Act of 1916 supported these efforts.
In spite of this activity, Wilson ran for re-election in 1916 on a WWI 'non-interference' platform. This included the slogan, 'he kept us out of war'.
Wilson was duly re-elected, with no Democratic challenger. He narrowly beat his Republican opponent, Supreme Court Justice Charles Evans Hughes. The Wilson campaign played on fears that a Republican president would lead the US into WWI.
However, German provocation escalated at the beginning of 1917, with a larger scale resumption of unrestricted submarine warfare against ships in British waters. Germany’s aim was to defeat the Allied Powers before America was fully mobilised to join the conflict.
At the beginning of 1917, public support for the US entering the war coalesced with the emergence of the Zimmermann telegram, named for Arthur Zimmermann, German State Secretary for Foreign Affairs.
Intercepted and decrypted by British intelligence in January, the diplomatic communication from the German Foreign Office revealed a proposal for Mexico to join the war. Among other things, it outlined that Germany would aid Mexico in efforts to retake its former territory in Texas, Arizona, and New Mexico.
Pressure intensified as Germany’s unrestricted submarine warfare tactic led to increased attacks on US ships. In March 1917, Wilson’s Cabinet lent its support to the country entering WWI.
The following month, President Wilson addressed Congress. His request for a declaration of war against Germany (and later Austria-Hungary) included a call for an increase in taxes. He also proposed a military draft to increase troop numbers.
The target was a Regular Army of 300,000 and a National Guard of 400,000, supplemented by a National Army of 500,000, to be established through the use of conscription. In total, 4.8 million Americans would serve in uniform during the remaining months of WWI.
US soldiers on the WWI battlefield
In June 1917, US soldiers (nicknamed 'doughboys') arrived in France, under the command of General John J. Pershing. At the time, the fighting was at a stalemate, with the Allied forces reeling from failures on the battlefield and the so-called 'French Army mutinies'.
The first engagement for the American Expeditionary Forces (AEF) involved US Army engineers at the Battle of Cambrai in November and December 1917.
Initially, General Pershing was insistent that AEF would operate as an independent force under US command. However, a series of German attacks in early 1918 (the Spring Offensive) led to AEF soldiers being sent to reinforce Allied armies.
AEF engaged in its first major action of the war during the Third Battle of the Aisne in May and June 1918. At the minor Battle of Cantigny, US troops captured the German-held village.
Over the next six months, US troops were involved in a dozen WWI battles on the Western Front. These included:
Battle of Belleau Wood
In June 1918, the US Army's 2nd and 3rd Divisions, along with French and British forces, halted the advance of German troops and took back Belleau Wood, with 1,811 US soldiers killed. The 4th Marine Brigade was especially distinguished. The battle remains a notable achievement for the US Marines and resulted in Belleau Wood being renamed 'Bois de la Brigade de Marine'.
Battle of Château-Thierry
Fought on 1st July 1918, the Battle of Château-Thierry was part of the Second Battle of the Marne. In conjunction with French forces, the 3rd Brigade of the 2nd US Division drove back German forces and took the strategic town of Vaux. The battle marked a turning point in the war in the Allies’ favour. It resulted in 1,908 US casualties.
Battle of Saint-Mihiel
Between 12th and 15th September 1918, AEF and French troops attacked vulnerable German forces at the Saint-Mihiel salient (a battlefield feature which projects into enemy territory). It was the first large-scale offensive launched by the Americans and proved the ability of the AEF to operate under US command. The battle involved the US Army Air Service (which later became the US Air Force) and tank assaults led by then Lieutenant Colonel George S. Patton. It resulted in 7,000 US casualties.
The Battle of Saint-Mihiel set up the final, decisive action which brought the war to an end.
Ending the war
Lasting from August to November 1918, the Hundred Days Offensive was a co-ordinated Allied effort across the Western Front that neutralised German defences.
On 26th September, General Pershing and his successor Lieutenant General Hunter Liggett led over one million soldiers in the Meuse-Argonne Offensive, which remains the largest battle in US history. Over 47 days, AEF soldiers drove German troops back 40 miles to Sedan, a railway hub close to the Belgian border. It resulted in 120,000 US casualties, with 26,000 killed.
Meuse-Argonne ended the Hundred Days Offensive and brought the two sides to the table to finally end the four-year conflict.
The signing of an armistice between Germany and the Allies on 11th November 1918 signalled the end of WWI. A formal peace treaty, the Treaty of Versailles, was signed on 28th June 1919.
Notably, the US did not ratify the treaty due to criticism in some quarters over the perceived role of the League of Nations. The US signed a separate peace treaty with Germany, the Treaty of Berlin, on 25th August 1921.
US impact on WWI
AEF was initially unprepared for WWI, lacking troop numbers and training, notably in the trench warfare which was a key feature of the war. However, once they were fully mobilised and engaged, the participation of AEF troops broke the stalemate and turned the momentum of the war in favour of the Allies.
It is worth noting that the US played a wider role in the Allies’ victory as well as the battlefield. This included the use of Native American codebreakers, who helped the Allies keep their communications secret from the Germans. The efforts of these 'code talkers' were credited with bringing the war to an end earlier and in saving hundreds of thousands of lives.
The aftermath of The Great War
WWI is referred to as The Great War, due to its extent, severity, and impact. Indeed, to those who lived through it, WWI was 'a war to end all wars'. But just two decades later, Adolf Hitler's invasion of Poland led the UK and France to declare war on Germany once again.
In the years following WWI, America leaned towards policies of isolationism and non-interventionism, with Congress passing a series of Neutrality Acts. However, antiwar sentiments were set aside following Japan’s surprise attack on Pearl Harbor on 7th December 1941, which brought the US into WWII.
US sacrifice in WWI
Almost 177,000 US soldiers died in WWI, with 53,400 deaths on the battlefield, around half of which occurred during the Meuse-Argonne Offensive. The other deaths were caused by accidents and disease, particularly the 1918/19 influenza pandemic, which took the lives of an estimated 25,000 US soldiers.
In comparison, an estimated 750,000 soldiers were killed in total across the Union and Confederate sides in the US Civil War (1861-1865), and over 405,000 in WWII (1939-1945). The Vietnam War (1955-1975) resulted in 58,220 US deaths.
These sobering figures help to underline that while the US only entered WWI in 1917, the country’s involvement was significant, in terms of the outcome and the sacrifice.
