A Military alliance is an agreement between two, or more, countries; related to wartime planning, commitments, and/or contingencies; such agreements can be both defensive and offensive. Military alliances often involve non-military agreements, in addition to their primary purpose.

Historic Military Alliances

• Wars of Scottish Independence
  • Auld Alliance - Scotland, Norway, France
• Italian Wars
  • League of Cambrai - The Papal States, France, Aragon, Holy Roman Empire
  • Catholic League (Italian) - The Papal States, Venice, England, Aragon, Holy Roman Empire
• Wars of the Schmalkaldic League
  • Schmalkaldic League - German Protestant States
• Thirty Years War
  • Catholic League (German) - Bavaria, other Catholic German States
  • Protestant Union - Protestant German States
• War of the Grand Alliance (Nine Years War)
  • League of Augsburg - Holy Roman Empire, Spain, Austria, other German states
• War of the Spanish Succession
  • The Quadruple Alliance of 1718
• Napoleonic Wars
  • The Quadruple Alliance of 1814/15
  • First through Seventh Coalitions
• The Quadruple Alliance of 1834
• League of Nations
• World War I
  • the Entente/the Allies - United Kingdom, France, Russia (to 1917), United States (from 1917)
  • the Central Powers - Germany, Austria-Hungary, Ottoman Empire
• World War II
  • the Axis - Germany, Japan, Italy, many others.
  • the Allies - United Kingdom, France, Soviet Union, United States, many others.
• Cold War
  • NATO -- United States, Canada, most of Western Europe (still an active alliance)
  • Warsaw Pact - Soviet Union, East Germany, Hungary, Poland, Czechoslovakia, Romania, Bulgaria
  • SEATO - United States, United Kingdom, France, Australia, New Zealand, Pakistan, Thailand, Phillippines
  • CENTO - United States, United Kingdom, Turkey, Iran, Iraq, Pakistan
  • ANZUS - United States, Australia, New Zealand (still active alliance)

Current Military Alliances

• North Atlantic Treaty Organization (NATO) - United States, Canada, most of Western Europe, parts of Eastern Europe
• Iraq war coalition - group of nations which have offered various degrees of support for the 2003 invasion of Iraq.
• Collective Security Treaty Organization (CSTO) - Russia, Belarus, Armenia, Kazakhstan, Kyrgyzstan, Tajikistan. (see CIS article for details.