Explain the main reasons the Allies defeated Germany by 1918, including the entry of the United States, the naval blockade, and new tactics

What this dot point is asking

This dot point asks you to explain why the Allies, mainly Britain, France and later the United States, defeated Germany and its partners by 1918. After years of stalemate, the balance finally tipped, and you should be able to explain the main reasons. The strongest answers do not just list reasons but explain how they worked together: Germany was slowly worn down while the Allies grew stronger, above all once the United States joined. Your judgement should weigh which reasons mattered most.

The answer

The entry of the United States

The single most important change was the entry of the United States into the war in 1917. The United States was a huge, wealthy and growing country that had stayed out of the fighting. Germany's use of submarine warfare to sink ships, including ships carrying American passengers and goods, helped push the United States to join the Allies. American entry brought fresh soldiers, vast amounts of money, food and equipment, and a great boost to Allied morale. For an exhausted Germany, the arrival of a powerful new enemy that it could not match was a disaster.

The British naval blockade

For most of the war the British navy controlled the seas and used a naval blockade to cut off Germany from overseas trade. This meant Germany could not easily import food, fuel and raw materials. Over time the blockade caused serious shortages inside Germany. Ordinary people went hungry, factories ran short of materials, and discontent grew on the home front. The blockade did not win the war on its own, but it slowly drained Germany's strength and its people's will to keep fighting.

Germany's failed gamble in 1918

By early 1918 Germany knew that American troops would soon arrive in huge numbers. So it launched a massive offensive in the spring of 1918, gambling everything on a knockout blow before the Americans were ready. At first the attack made big gains, but it could not be sustained. The German troops were exhausted, supplies could not keep up, and the offensive ran out of strength. The Allies, strengthened by fresh American forces, then counter-attacked and pushed the Germans back.

Germany's exhaustion and collapse

By the second half of 1918, Germany was exhausted in every way. Its armies were worn out and falling back, its allies were dropping out of the war, and its people were hungry and angry because of the blockade. Unrest spread at home, and the German government lost control of the situation. With no hope of winning, Germany asked for an armistice, an agreement to stop fighting, which came into effect on 11 November 1918. The war was over, and the Allies had won.

Weighing the reasons

To reach a judgement, think about how the reasons connect. The blockade weakened Germany slowly over years. The entry of the United States added overwhelming new strength to the Allies. Germany's failed 1918 gamble used up its last reserves at the worst possible moment. Behind all of these lies one big theme: the Allies could call on far greater resources and manpower than Germany, and over a long war this advantage proved decisive. Most answers conclude that American entry was the factor that tipped the balance, with the blockade as the slow-acting cause underneath.

Examples in context

Example 1. Submarine warfare and US entry. Germany tried to use submarines to sink the ships supplying Britain, including neutral and passenger ships. This unrestricted submarine warfare angered the United States and was one of the main reasons it joined the Allies. Germany's gamble at sea thus helped bring in the very power that would tip the war against it.

Example 2. Hunger on the German home front. By the later years of the war, the blockade had made food so scarce in Germany that people queued for tiny rations and many went hungry. This hardship sapped the nation's will to fight and led to strikes and unrest. The collapse of morale at home was as important as defeat at the front in forcing Germany to give up.

Try this

• Cue. Explain why the entry of the United States in 1917 was so important, naming what it brought to the Allies.

• Cue. Describe the British naval blockade and explain how it weakened Germany's home front over time.

• Cue. Explain why Germany's spring 1918 offensive failed and what happened next, then give your judgement on the most important reason the Allies won.