On 1 December 1916 the Romanian army threw its last reserves against the flank of August von Mackensen's Danube Army on the Neajlov River, southwest of Bucharest. The counterattack, directed by General Constantin Prezan, gained ground and took prisoners at first, but the Germans had captured the Romanian battle orders, and by 3 December the attack had collapsed. Bucharest fell on 6 December.
Two armies closing on the capital
Romania entered the war on the Allied side in August 1916 and sent its army into Transylvania. The Central Powers answered on two fronts. Erich von Falkenhayn's Ninth Army threw the Romanians back and, in November, broke through the Carpathian passes into Wallachia, while Mackensen's forces came up from Bulgaria and crossed the Danube. The historian Sorin Cristescu, speaking to Radio Romania International, places the crossing at Zimnicea. By the end of November the two enemy armies were converging on Bucharest.1
Romania still kept the Julian calendar, so Romanian accounts date the battle that followed from 16/29 November to 20 November/3 December 1916, giving the old and new style dates together. Romanian historians call it the battle of the Argeș and Neajlov, or simply the battle for Bucharest.2
Prezan's gamble
General Constantin Prezan took charge of the defense of the capital. His idea, as Cristescu describes it, was to slip between the two German armies and beat them one at a time, while waiting for Russian help that came late. Falkenhayn later summed up the Romanian plan in a note quoted by the Romanian magazine Historia: the 1st Army, about four divisions, would hold the line of the Argeș, while a maneuver group of four infantry divisions and a cavalry division struck the left flank of Mackensen's Danube Army, and two Russian divisions pinned its right wing. Falkenhayn judged the plan not a bad one, except that it ignored the German force under Kühne coming up from the west. According to the historian George Marcu, quoted by Adevărul, Romanian appeals for more Russian troops brought no real result.3
The blow fell across the Neajlov. Adevărul's account, drawing on Marcu and on the historian Constantin Vărzaru, says that on 1 December the Romanians won successes in every sector. Historia describes a column of nearly 2,000 German prisoners marched along Calea Victoriei, the main avenue of Bucharest.4
The captured orders
Then the plan was lost. A Romanian staff car carrying operation orders fell into German hands. In Falkenhayn's note, the order was beyond doubt genuine, taken from two Romanian staff officers who had driven between the lines; Historia places the capture at Rătești, where the car ran into a German regiment on the march. The Germans now knew where the Romanian units stood and what they intended. Cristescu, for his part, argues that German numbers and skill would have decided the battle even without the lost car.5
On 3 December, the decisive day in Historia's account, German divisions fell without warning on the rear of the Romanian forces between the Neajlov and the Argeș. By the morning of 4 December the whole line of the Argeș was in enemy hands, and nothing stood between the Central Powers and the capital.6
The fall of Bucharest
Bucharest's ring of forts had been stripped before Romania went to war, and by 4 December the city could not be defended. The decision to give it up without a fight was taken on 6 December, Mackensen's birthday, and Bucharest fell that day. The court and the government moved north to Iași, in Moldavia.7
The rest of the Romanian army fell back into Moldavia, where Russian troops finally came to its support. Gerhard Hetzer, writing for the Freie Universität Berlin, notes that about two thirds of the country was occupied, that Mackensen became its military governor, and that British detachments set fire to the oil fields at Ploiești to keep them out of German hands. The Central Powers gained Romania's wheat and oil, and Russia had another 300 miles of front to hold. The occupation of Bucharest lasted until November 1918.8
