The Romanian Campaign was a campaign in the Balkan theatre of World War I, with Romania and Russia allied against the armies of the Central Powers.
The Romanian government signed a treaty with the Allies on August 17, 1916 and declared war on the Central Powers on August 27. The Romanian Army was quite large, over 500,000 men in 23 divisions. However, it had officers with poor training and equipment; more than half of the army was barely trained. Meanwhile, the German Chief of Staff, General Erich von Falkenhayn correctly reasoned that Romania would side with the Allies and made plans to deal with Romania. Thanks to the earlier conquest of Serbia and the ineffective Allied operations on the Greek border, and having a territorial interest in Dobrogea, the Bulgarian Army and the Ottoman Army were willing to help fight the Romanians.