Russia was not an ally of Germany in World War 1.
Germany failed to renew their treaty or promise they made with Russia in 18 something or other. therefore Russia was free to ally with the Allied forces(countries lke England, France, etc.)
The UK declared war on Germany in 1939 because Germany invaded Poland, a British ally.
Canada
Romania was an ally of Germany.Romania was an ally of Germany.
Serbia was not allied with Germany; Italy and Romania, yes.
Germany was on the side of the Central Powers which consisted of Germany, Austria-Hungary, the Ottoman Empire (modern day Turkey), and Bulgaria.
The Austro/Hungarian Empire was Germany's ally in WW1
Believed it or not : Germany read about : The German-Soviet Treaty of Friendship, Cooperation and Demarcation
Zimmerman
In the WW2 Romania was an ally of Germany between 22.06.1941 and 23.08.1944.
Germany