Prior to World War I, the countries of Europe were competing in their own form of 'Cold War.' Each country was building up defenses, colonial possession, and treaties against the group that they were the most fearful of. The three institutions that placed Europe into World War I were: Imperialism, Nationalism, and Colonialism. The countries of Europe were racing around the world to acquire the most land to develop. Africa, Southeast Asia, and parts of Latin America were fair game. Because of the emergence of mercantilism and the desire for more products to develop and sell the countries of Europe aggressively pushed their international influence.

Once the war began in 1914, there were two sides, the Central Powers and the Allies.


Central Powers
       
Austria-Hungary
Germany
Bulgaria
Ottoman Empire
    ALLIES
       
France
Great Britain
Serbia
Italy
       
Russia
United States
Japan
Belgium
A total of 20 countries including their possessions like Great Britain (6 colonies) along with 14 other countries that didn't even have a military declared war on the Central Powers. Some of these countries were hoping to side up with the above mentioned countries, but others were hoping when the war was over they could try to negotiate new territories which they could obtain through their own personal abilities.
By the end of the 19th century, Great Britain controlled 1/5 of the world's landmass. The United States was not even a top 10 power in the world. However at the turn of the century the United States economy was operating in the black (good) and the presidents of the United States ordered a massive over haul of the United States Navy. Germany was becoming ambitious as they continued to follow the creed of the dead Otto von Bismarck, "Iron and Blood." The Italians and Germans caused a major shake-up in Europe. A key issue found in all of Europe was militarism. Militarism is the glorification of military power; war was seen as a way to show strength and financial power. If you could sustain an economy and win at war, then you are economically and militarily strong enough to prosper in times of peace.
Otto von Bismarck of Germany was masterful at manipulating situations politically to benefit the Germans in the 1860's and 1870's. His political work held weight long after his death. Bismarck created a triple alliance with Italy and Austria to protect the Germans from retaliation by the French. He then created a treaty with Russia for more protection. After Bismarck was let go by the German government, the treaty with Russia lapsed and France and Russia signed a treaty together. France wanted their revenge while it was Russia's goal to control the Slavic population in the Ottoman and Austria-Hungarian Empires. As the Ottoman Empire was in decline, the Serbs were gaining their independence. The territories of Bosnia-Herzegovina were desired because of their access to the sea. In 1908 Austria annexed these territories, which angered the Serb nationalists.
The spark that set everything off was the assassination of Archduke Francis Ferdinand on June 28, 1914. While touring the Empire in the city of Sarajevo a member of a radical group called the Black Hand, Gabriel Princip shot the Archduke in his car. All the prior treaties were activated and within weeks Europe was a war with each other. Battles were fought all over Europe. There was a Western Front in France, Eastern Front in Russia, a Serbian Campaign, Gallipoli Campaign, fighting in the Middle East, Atlantic Ocean, and technically the first battle was fought in the Pacific Ocean.
The execution of World War I was not what any of the participating countries expected. The biggest problem is that the countries were using 19th century battle techniques with 20th century weapons. At the beginning of the war, many battles were encumbered with needless slaughter. For example, France started the war in their old blue uniforms like they wore when Napoleon was in control 100 years earlier. While wearing these bright blue uniforms, they marched in straight lines right into German machine gun nests. The French commander believed that he beat the Germans by sending wave after wave of men, but he neglected to adjust machine guns over single shot rifles. Also, he believed that the fear of the blue uniforms would strike fear in the Germans by drumming up the greatness of the French Napoleon armies. It was so bad the Germans looked at their officers wondering if they still had to slaughter the French.

As the war progressed each side tried to deliver a knockout blow and they became embedded into trench warfare. The Germans caught a break when the Russians left during the war because of their revolution, but the war became a war of atrocity. Eventually Austria and Bulgaria left and the Germans were left to fight alone. The United States stayed neutral until 1917 when they discovered the Zimmerman note which was a note from the Germans to the Mexicans stating if they attacked the United States, the Germans would help Mexico get the states of Arizona, New Mexico, and California.

In your junior year your social studies classes will cover the actual war in more detail, for the purpose of this class, we are only looking at the impact that World War I had in terms of world events. The goal of the Allies was to starve the Germans into submission. It was a slow and steady process, but by 1919 the German people were on the verge of starvation and despair. During World War I, the Germans never lost a major battle, however they had to surrender because of the blockade. This disillusionment along with the fact that there never was a deciding battle ending World War I made the German soldiers and people lost for answers. This void of leadership and need for answers help open the door for the Nazi party in the 1920's.

Once negotiations started Europe and the United States had different ideas about post-war Germany. The United States under President Woodrow Wilson pushed for more mercy towards Germany and proposed the League of Nations. The League of Nations was a precursor to the United Nations that was created after World War II. The most damaging blow to the League of Nations was that the United States Congress didn't approve the United States' participation in the League. Europe wanted the punish Germany for World War I and the Treaty of Versailles almost guaranteed a World War II because of the punished placed upon Germany. Besides the impact on Germany and the boundary lines of Europe the Treaty of Versailles also dealt with the breaking up of Germany's colonial territories. Colonial territories around the world were classified into three categories:
Class A: Arab Territories suitable for self-government in a short period of time. Britain: Palestine, Iraq, and Trans Jordan; France: Syria and Lebanon.

Class B: Germany's colonies in Africa, able to self-rule in several decades.

Class C: Colonies need to stay under the rule of other nations for an indefinite period. Germany's territories in the Pacific and SW Africa; Japan: Pacific Territories; South Africa: SW Africa

Early lines were starting to be drawn in the Middle East when Great Britain was allowing European Jews to settle in the Holy Land, and Vietnam starts to become a major colony for the French. Both of these territories hold significant history for the United States and the World after World War II and during the Cold War.