France
Britain had a treaty to protect the neutrality of Belgium.
In the period before World War 1 it was: Germany, Austria-Hungary and Italy. However, Italy had joined hastily in 1882, had claims on Austrian territory and did not fight alongside Austria-Hungary and Germany in World War 1. In fact, in 1915 it entered th war on the side of the Entente. For more info on the tripple alliance, check out http://en.wikipedia.org/wiki/Triple_Alliance_(1882)
The Triple Alliance, aka The Central Powers. The main alliance included Germany, Italy, and Austria-Hungary. The Ottoman Empire also sided with Germany. Towards the end of the war, Italy joined the Entente and ceded from The Triple Alliance.
Britain declared war on Germany because Germany attacked Belgium in order to strategically invade France. Britain vowed to protect Belgium, so Britain joined World War I.
France
the triple entente
In the 1879, the Dual alliance (Germany and Austria) was made and then Italy joined in 1882 which made the Triple alliance.
Germany joined Austria-Hungary and Italy to create the triple alliance.
The Triple Alliance between Germany, Austria-Hungry and Italy was a secret alliance formed in May 1882. While no one joined the alliance in 1915, Italy did leave the alliance and join the allies.
Italy
Germany created the Triple Alliance to prevent a two front war.
West Germany joined NATO in 1955.
West Germany joined NATO in 1955.
Bulgaria
Japan joined Germany & Italy in a military alliance called the "Tripartite" or "Axis" powers on September 27, 1940.
no one. they joined an alliance with Germany in 1940