During World War I, the German Empire was one of the Central Powers. It began participation in the conflict after the declaration of war against Serbia...

start of World War I, Polish territory was divided between the Russian, German and Austro-Hungarian empires, and became the scene of many operations of the...

Станислав Кельнер History of Germany during World War I Hungary in World War I Invasion of Serbia by Bulgaria during the First World War Salzburg Negotiations...

was a leading Allied Power during the First World War of 1914–1918. They fought against the Central Powers, mainly Germany. The armed forces were greatly...

Technology during World War I (1914–1918) reflected a trend toward industrialism and the application of mass-production methods to weapons and to the technology...

see Diplomatic history of World War I. Below is a table showing the outbreaks of wars between nations which occurred during World War I. Indicated are...

Australia, the outbreak of World War I was greeted with considerable enthusiasm. Even before Britain declared war on Germany on 4 August 1914, the nation...

During World War I and World War II, Switzerland maintained armed neutrality, and was not invaded by its neighbors, in part because of its topography,...

participated in World War I from 1914 to 1918 as a member of the Allies/Entente and played an important role against the Imperial German Navy. Politically...

At the onset of World War I, Vietnam, nominally under the Nguyễn dynasty, was under French protectorate and part of French Indochina. While seeking to...

history of Canada in World War I began on August 4, 1914, when the United Kingdom entered the First World War (1914–1918) by declaring war on Germany...

The Kingdom of Bulgaria participated in World War I on the side of the Central Powers from 14 October 1915, when the country declared war on Serbia, until...

Germany entered into World War I on August 1, 1914, when it declared war on Russia. In accordance with its war plan, it ignored Russia and moved first...

During World War I (1914–1918), Brazil initially adopted a neutral position, in accordance with the Hague Convention, as an attempt to maintain markets...

China participated in World War I from 1917 to 1918 in an alliance with the Entente Powers. Although China never sent troops overseas, 140,000 Chinese...

diplomatic history of World War I covers the non-military interactions among the major players during World War I. For the domestic histories of participants...

War (1936–1939), and the Second Sino-Japanese War (1937–1945). Strategic bombing during World War II in Europe began on 1 September 1939 when Germany...

The use of slave and forced labour in Nazi Germany (German: Zwangsarbeit) and throughout German-occupied Europe during World War II took place on an unprecedented...

from the start of World War I in 1914 until early 1916. However, in that year and a half there were many hostile engagements between Germany and Portugal...

Empire was one of the Central Powers of World War I, allied with the German Empire, Austria-Hungary, and Bulgaria. It entered the war on 29 October 1914...

Although a member of the Triple Alliance, Italy did not join the Central Powers – Germany and Austria-Hungary – when the war started with Austria-Hungary's...

to an unprecedented degree. All of the powers used lessons from their experiences on the home front during World War I. Their success in mobilizing economic...

outbreak of World War I, Ukraine was not an independent political entity or state. The majority of the territory that makes up the modern country of Ukraine...

This is a timeline of declarations of war during World War II. A declaration of war is a formal act by which one nation goes to war against another. The...

atrocity propaganda as a way of mobilising public opinion against Imperial Germany and the Central Powers during the First World War. For the global picture...

following its long-standing policy of neutrality since the Napoleonic Wars, remained neutral throughout World War I between 28 July 1914 and 11 November...

neutral throughout World War I between 28 July 1914 and 11 November 1918, and despite domestic economic difficulties, it was considered "one of the most important...

The economic history of World War I covers the methods used by the First World War (1914–1918), as well as related postwar issues such as war debts and reparations...

The total number of military and civilian casualties in World War I was about 40 million: estimates range from around 15 to 22 million deaths and about...

The German occupation of Belgium (French: Occupation allemande, Dutch: Duitse bezetting) of World War I was a military occupation of Belgium by the forces...