Armistice of 11 November 1918 in the context of "Allied intervention in the Russian Civil War"

The Weimar Republic was a historical period of the German state from 9 November 1918 to 23 March 1933, during which it was a constitutional republic for the first time in history. The state was officially named the German Reich; it is also referred to, and unofficially proclaimed itself, as the German Republic. The period's informal name is derived from the city of Weimar,where the republic's constituent assembly took place. In English, the republic was usually simply called "Germany", with "Weimar Republic" (a term introduced by Adolf Hitler in 1929) not commonly used until the 1930s. The Weimar Republic had a semi-presidential system.

At the end of the First World War (1914–1918), the German Empire was economically and militarily exhausted and sued the Allies for peace. Awareness of an imminent defeat sparked the German revolution, the abdication of Kaiser Wilhelm II, the collapse of the Empire and the proclamation of the Weimar Republic. Hostilities in the war formally ceased with the Armistice of 11 November 1918.

The 1918 United Kingdom general election was called immediately after the Armistice with Germany which ended the First World War, and was held on Saturday, 14 December 1918. The governing coalition, under Prime Minister David Lloyd George, sent letters of endorsement to candidates who supported the coalition government. These were nicknamed Coalition Coupons, and led to the election being known as the "coupon election". The result was a massive landslide in favour of the coalition, comprising primarily the Conservatives and Coalition Liberals, with massive losses for Liberals who were not endorsed. Nearly all the Liberal MPs without coupons were defeated, including party leader H. H. Asquith.

It was the first general election to be held after enactment of the Representation of the People Act 1918. It was thus the first election in which women over the age of 30 (with some property qualifications), and all men over the age of 21, could vote. Previously, all women and many poor men had been excluded from voting. Women generally supported the coalition candidates.

The Polish–Soviet War (14 February 1919 – 18 March 1921) was fought primarily between the Second Polish Republic and the Russian Soviet Federative Socialist Republic, following World War I and the Russian Revolution.

After the collapse of the Central Powers and the Armistice of 11 November 1918, Vladimir Lenin's Soviet Russia annulled the Treaty of Brest-Litovsk and moved forces westward to reclaim the Ober Ost regions abandoned by the Germans. Lenin viewed the newly independent Poland as a critical route for spreading communist revolutions into Europe. Meanwhile, Polish leaders, including Józef Piłsudski, aimed to restore Poland's pre-1772 borders and secure the country's position in the region. Throughout 1919, Polish forces occupied much of present-day Lithuania and Belarus, emerging victorious in the Polish–Ukrainian War. However, Soviet forces regained strength after their victories in the Russian Civil War, and Symon Petliura, leader of the Ukrainian People's Republic, was forced to ally with Piłsudski in 1920 to resist the advancing Bolsheviks.

The German colonial empire (German: deutsches Kolonialreich) constituted the overseas colonies, dependencies, and territories of the German Empire. Unified in 1871, the chancellor of this time period was Otto von Bismarck. Short-lived attempts at colonization by individual German states had occurred in preceding centuries, but Bismarck resisted pressure to construct a colonial empire until the Scramble for Africa in 1884. Claiming much of the remaining uncolonized areas of Africa, Germany built the third-largest colonial empire at the time, after the British and French. The German colonial empire encompassed parts of Africa and Oceania.

Germany lost control of most of its colonial empire at the beginning of the First World War in 1914, but some German forces held out in German East Africa until the end of the war. After the German defeat in World War I, Germany's colonial empire was officially confiscated as part of the Treaty of Versailles between the Allies and German Weimar Republic. Each colony became a League of Nations mandate under the administration, although not sovereignty, of one of the Allied powers. Talk of regaining the colonies persisted in Germany until 1943, but never became an official goal of the German government.

The Meuse–Argonne offensive (also known as the Meuse River–Argonne Forest offensive, the Battles of the Meuse–Argonne, and the Meuse–Argonne campaign) was a major part of the final Allied offensive of World War I that stretched along the entire Western Front. It was fought from September 26, 1918, until the Armistice of November 11, 1918, a total of 47 days. The Meuse–Argonne offensive was the largest in United States military history, involving 1.2 million American soldiers, sailors and marines, along with 800,000 French and 850 Siamese personnel. It is also the deadliest campaign in the history of the United States Army, resulting in over 350,000 casualties, including 28,000 German lives, 26,277 American lives and an unknown number of French lives. American losses were worsened by the inexperience of many of the troops, the tactics used during the early phases of the operation, and the widespread onset of the global influenza outbreak called the "Spanish flu."

The offensive was the principal engagement of the American Expeditionary Forces (AEF) in World War I. It was one of a series of Allied attacks, known as the Hundred Days Offensive, which brought the war to an end. It was the largest and bloodiest operation of the entire war for the AEF even though, given the scale of other battles on the Western Front, its size was limited and the operation itself secondary, being far from the main offensive axis.

The identification of the causes of World War I remains a debated issue. World War I began in the Balkans on July 28, 1914, and hostilities ended on November 11, 1918, leaving 17 million dead and 25 million wounded. Moreover, the Russian Civil War can in many ways be considered a continuation of World War I, as can various other conflicts in the direct aftermath of 1918.

Scholars looking at the long term seek to explain why two rival sets of powers (the German Empire, Austria-Hungary, and the Ottoman Empire against the Russian Empire, France, and the British Empire) came into conflict by the start of 1914. They look at such factors as political, territorial and economic competition; militarism, a complex web of alliances and alignments; imperialism, the growth of nationalism; and the power vacuum created by the decline of the Ottoman Empire. Other important long-term or structural factors that are often studied include unresolved territorial disputes, the perceived breakdown of the European balance of power, convoluted and fragmented governance, arms races and security dilemmas, a cult of the offensive, and military planning.

A PT boat (short for patrol torpedo boat) is a motor torpedo boat used by the United States Navy in World War II. These vessels were small, fast, and inexpensive to build, and were valued for their maneuverability and speed. However, PT boats were hampered at the beginning of the war by ineffective torpedoes, limited armament, and comparatively fragile construction that limited some of the variants to coastal waters. In the US Navy they were organized in Motor Torpedo Boat Squadrons (MTBRONs).

PT boats were very different from the first generation of torpedo boats, which had been developed at the end of the 19th century and featured a displacement hull form. These first generation torpedo boats rode low in the water, displaced up to 300 tons, and had a top speed of 25 to 27 kn (46 to 50 km/h). During World War I Italy, the US, and UK developed the first high-performance, gasoline-powered motor torpedo boats (often with top speeds over 40 kn (74 km/h)) and corresponding torpedo tactics, but these projects were all quickly disbanded after the Armistice. Design of World War II PT boats continued to exploit some of the advances in planing hull design borrowed from offshore powerboat racing and used multiple lightweight but more powerful marinized aircraft-derived V-12 engines, and thus were able to advance in both size and speed.