1. The First World War

2. American Power Tips the Balance
America was not ready for war. Only 120,000 men were in service when war was declared, so Congress passed the Selective Service Act in May of 1917.
By the end of 1918, 24 million had signed up and almost 5 million had been called to duty. About 2 million American troops reached Europe altogether.

3. Fresh U.S. Soldiers Join Fight
After 2 ½ years of fighting, the Allied forces were exhausted. One of the main contributions of the Americans was fresh and enthusiastic troops. American infantry were nicknamed “doughboys”. The reasons for this nickname are anecdotal and often disputed.
Most doughboys had never ventured far from the farms or small towns they had grown up in.

4. Important New Weapons
Machine Guns: Guns could now fire 600 rounds per minute.
The Tank: New steel tanks ran on caterpillar treads.
Airplanes: Early dogfights resembled duals, however by 1918 the British had a fleet of planes that could deliver bombs.
Poison Gas: Mustard gas was used to subdue the enemy.

5. Other Weapons & Equipment
Howitzers
Flame throwers
Torpedoes
U-boats
Phosphorus grenades
Field phones
Search lights
Gas masks
Camouflage
Railroad guns
Blimps

6. Both humans and animals were susceptible to the effects of poison gas
Both humans and animals were susceptible to the effects of poison gas. Dogs were used during World War I as sentries, sled dogs, pack animals, and messengers.

7. American Troops Go On the Offensive
When Russia surrendered to the Germans in 1917, the Central Powers were able to focus on the Western Front . By May, the Germans were within 50 miles of Paris. The First Division of American soldiers landed at the ports of the French town of St. Nazaire in late June The sight of the fresh American soldiers had an amazing effect on French morale.
Men of the 42nd Division during the Second Marne. These men were killed by artillery fire just 5 minutes after this photo was taken

8. American Contributions to WWI
The Allied commanders arranged for a grand reception for the Americans on the Fourth of July in Paris.
The Second Battalion of the First Division’s 16th Infantry, headed by General John J. Pershing, marched through the streets of Paris on July 4, 1917.
Jubilant Parisians assembled at the tomb of the Marquis de Lafayette, who had famously fought in the American Revolution.

9. American Contributions to WWI
The arrival of the rest of the American Expeditionary Force started soon after. The Second Division began arriving in small numbers in late August 1917 and were still arriving in the spring of 1918. 
Americans played smaller, defensive roles in the early battles of “The Hundred Days Offensive” at battles like Amiens and Cambrai in 1917, but the majority of American Battles in WW1 were fought in 1918. 
Together, the Allies attacked the Central Powers in a loose but ever-tightening semicircle, continually pushing the Germans back eastward across France, showing amazing success at breaking through the German lines again and again.

11. The Hundred Days Offensive
Allies:
British: United Kingdom, Canada, Australia, New Zealand, India, Newfoundland, South Africa
French
United States
Belgium
Portugal
Central Powers:
Germany
Austria-Hungary
Major American Campaigns in March – November 1918:
Somme Defensive
Lys
Cantigny
Noyon
Marne
Aisne
St. Mihiel
Argonne

12. Germany Collapses, War Ends
On November 3, 1918, Germany’s partner, Austria-Hungary, surrendered to the Allies. That same day, German sailors mutinied against their government.
Other revolts followed, and Germany was too exhausted to continue.
So at the eleventh hour, on the eleventh day, of the eleventh month of 1918, Germany signed a truce ending the Great War.
War ends 11/11/18