Editing Ferdinand I of Romania (section)

===World War I===
{{Further|Romania during World War I|Diplomatic history of World War I# Romania}}

Though a member of a cadet branch of [[German Empire|Germany]]'s ruling [[Hohenzollern]] imperial family, Ferdinand presided over his country's entry into [[World War I]] on the side of the [[Triple Entente]] against the [[Central Powers]], on 27 August 1916. Thus he gained the sobriquet "the Loyal", having kept the oath he swore before the [[Romanian Parliament]] in 1914: "I will reign as a good Romanian."

[[File:WWI Poster Rumania.jpg|thumb|Wilhelm and Ferdinand (British [[World War I]] poster)]]
As a consequence of this "betrayal" of his German origin, [[German Emperor]] [[Wilhelm II]] had Ferdinand's name erased from the Hohenzollern House register.

Despite the setbacks after the entry into war, when [[Dobruja]] and [[Wallachia]] were occupied by the Central Powers, Romania fought in 1917 and stopped the German advance into [[Moldavia]]. When the new [[Bolshevik]] government of Russia [[Treaty of Brest-Litovsk|sued for peace in 1918]], Romania was surrounded by the Central Powers and forced to conclude [[Treaty of Bucharest (1918)|a peace treaty of its own]]; however, Ferdinand refused to sign and ratify the Treaty of Bucharest. Allied forces then advanced on the [[Thessaloniki]] front and they knocked Bulgaria out of the war. Ferdinand ordered the re-mobilization of the [[Romanian Army]], and Romania re-entered the war on the side of the Triple Entente.