Battle of Transylvania

Battle of Transylvania
Part of the Romanian Campaign of World War I
Romanian troops crossing the mountains into Transylvania
Date 27 August 1916 — 25 October 1916 Location Transylvania, present-day Romania Result Central Powers victory after initial Romanian advance
Belligerents
Romania  Russian Empire	Austria-Hungary  German Empire
Commanders and leaders
Ioan Culcer Alexandru Averescu Constantin Prezan	Arthur Arz von Straußenburg Erich von Falkenhayn
Units involved
1st Army 2nd Army 4th Army	1st Army 9th Army
Strength
440,000 (initially)	70,000 (initially)
Casualties and losses
Unknown	Unknown

Battle of Oltenia
Part of the Romanian Campaign of World War I
Date 26 October 1916 — 26 November 1916 Location Oltenia, present-day Romania Result Central Powers victory
Belligerents
Romania	German Empire  Austria-Hungary
Commanders and leaders
Ioan Culcer Ion Dragalina Nicolae Petala Paraschiv Vasilescu	Erich von Falkenhayn Viktor Kuhne
Units involved
1st Army	Army Group Kühne
Strength
Unknown	80,000 troops 30,000 horses
Casualties and losses
Unknown	Unknown

The Battle of Transylvania was the first major operation of the Romanian forces Campaign during World War I, beginning on 27 August 1916. It started as an attempt by the Romanian Army to seize the disputed province of Transylvania, and potentially knock Austria-Hungary out of the war. Although initially successful, the offensive was brought to a halt after Bulgaria's attack on Dobruja. Coupled with a successful German and Austro-Hungarian counterattack after September 18, the Romanian Army was eventually forced to retreat back to the Carpathians by late October.

Before the war, the Kingdom of Romania was an ally of Austria-Hungary; however, when war broke out in 1914 Romania pledged neutrality - claiming that Austria-Hungary had started the war and thus Romania had no obligation to join it. Romania eventually joined the Entente, on the condition that the Allies recognise Romanian authority over Transylvania; Romanians being the majority population in the region. The Allies accepted the terms, and Romania declared war on Austria-Hungary on 27 August.

On the night of 27 August, three Romanian armies crossed the largely undefended Carpathian passes, meeting only sporadic resistance by Austro-Hungarian border units. The Romanian plan (Hypothesis Z) called for a rapid advance to the strategically important Mureş River with Budapest as the ultimate target. The main advance was carried on by the Second Army, with the First and Fourth on its flanks. The second Army crossed the border on the night of 27–28 August and advanced into Transylvania.

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Wikipedia