France and Germany are the two key armies that clearly increased in size between 1870 and 1914, with both of their standing armies roughly doubling in this period. Many other major European powers also expanded their forces through higher military spending and conscription in the same era.

Main armies that grew

  • France’s standing army about doubled in size between the Franco‑Prussian War era (around 1870) and the outbreak of the First World War in 1914.
  • Germany’s standing army also doubled over the same period, reflecting its rising power and focus on militarism after unification.

Other great powers

  • Across Europe, the main great powers (Britain, France, Germany, Austria‑Hungary, Russia, Italy) sharply increased military budgets and enlarged their armies and navies in the decades before 1914.
  • Conscription policies were expanded or tightened in most continental states, which allowed them to maintain much larger armies in peacetime and mobilize millions more in war.

Why this buildup mattered

  • Rising nationalism and rivalry encouraged governments to pour money into armaments, leading to a four‑fold rise in combined military expenditure by the great powers from 1870 to 1914.
  • This arms and army buildup helped create the tense, heavily armed environment in which a regional crisis in 1914 could escalate into a full‑scale world war.

Information gathered from public forums or data available on the internet and portrayed here.