The four main causes of World War 1 are often remembered with the acronym MAIN: Militarism, Alliances, Imperialism, and Nationalism. These long-term forces built up tension across Europe for decades before the war finally broke out in 1914.
Steps
Militarism: European powers, especially Germany and Britain, competed in a massive arms race. Countries built up huge armies and navies, making war seem inevitable and normal.
Alliances: Europe split into two major alliance systems — the Triple Alliance (Germany, Austria-Hungary, Italy) and the Triple Entente (France, Russia, Britain). When one country went to war, its allies were pulled in too.
Imperialism: European nations competed to control colonies and resources around the world, especially in Africa and Asia. This rivalry increased distrust and jealousy between powers.
Nationalism: Intense national pride led countries to believe they were superior to others. In places like the Balkans, ethnic groups wanted independence, creating a powder keg of conflict.
The spark: The assassination of Archduke Franz Ferdinand of Austria-Hungary in June 1914 set off a chain reaction. Austria-Hungary blamed Serbia, alliances kicked in, and within weeks most of Europe was at war.
Worked example
Think of MAIN like building a bonfire: Militarism gathered the wood (weapons), Alliances stacked it together (everyone connected), Imperialism poured on fuel (competition for colonies), and Nationalism lit the kindling (pride and rivalry). The assassination of Franz Ferdinand was the match that set it all ablaze.
Remember
The four main causes of WW1 — Militarism, Alliances, Imperialism, and Nationalism (MAIN) — were long-term forces that made Europe a ticking time bomb well before 1914.