On 27 August 1916, the Kingdom of Romania declared war on Austria-Hungary and proceeded to invade the Hungarian region of Transylvania.

Opposing the Romanian invasion of Transylvania was the Austro-Hungarian 1st Army, led by General Arthur Arz von Straussenburg.

[1] Following Romania's declaration of war against Austria-Hungary on the evening of 27 August, General Culcer's Olt-Lotru Group began advancing towards Nagyszeben through the Turnu Roșu Pass.

The easternmost one, comprising the 1st Border Guard Regiment under Lieutenant-Colonel Gheorghe Cantacuzino, crossed the mountains to the east of the Turnu Roșu Pass, using paths known only to the locals.

After an entire day of fighting, they finally drove the gendarmes and soldiers north and took the village at the head of the pass.

Until the arrival of the Lotru Group, the Austro-Hungarians held their own, the Romanians making little progress against the spirited defenders of Colonel Arnold Barwick's 143rd Brigade.

The arrival of Colonel Moșoiu's forces turned the tide for the Romanians, causing the Austro-Hungarians to retreat to the heights on both sides of the city.

[3][4] Four miles east of the Turnu Roșu Pass, the Romanian 1st Border Guard Regiment drove back a Hungarian battalion, taking two villages by dawn on the 28th.

[7][8] Erich Ludendorff referred to this in his memoirs, stating that, after taking Brassó (Brașov/Kronstadt) on 29 August, "Rumanian patrols were soon seen in Hermannstadt.".