The Romanian Volunteer Corps in Russia (), or Volunteer Corps of Transylvanians-Bukovinians (Corpul Voluntarilor ardeleni-bucovineni, Corpul Voluntarilor transilvăneni și bucovineni), was a military formation of World War I, created from ethnic Romanian prisoners of war held by Russia. Officially established in February 1917, it comprised abjurers of the Austro-Hungarian Army, mainly contingents from Transylvania and Bukovina. These had been obliged to fight against Romania, and, once in Russian custody, volunteered for service against the Central Powers. As campaigners for self-determination and union with Romania, they passed political resolutions which, in both tone and scope, announced those adopted on Union Day 1918.
The Corps was effectively an active military reserve of the Romanian Land Forces, and regularly dispatched new units to the Romanian front after June 1917. It helped defend the last stretches of Romania against the Central Powers' unified offensive, and met success in the Battle of Mărășești, but it still lacked a unitary command structure. When the October Revolution in Russia and the Romanian armistice took Romania out of the Entente camp, the Corps was left without backing and purpose. However, it inspired the creation of similar units in Entente countries, most successfully the .
Mobilized volunteers or prisoners symbolically tied to the Corps were left behind in Russia after the Russian Civil War was ignited. Various such individuals formed the Romanian Legion of Siberia, which resisted the Bolsheviks in cooperation with the Czechoslovak Legions and the White movement. These units were ultimately repatriated to Greater Romania in 1920.
Darnytsia Corps
Origins
During 1916, Romania entered World War I as an Entente country, in alliance with the Russian Empire against Austria-Hungary and the other Central Powers. After a while, Romania began investigating the fate and loyalties of Austria-Hungarian Romanians who were held in Russian POW camps. Estimates for that period place the total population of Bukovinian and Transylvanian Romanians in such facilities, throughout Russia, at 120,000 or 130,000. Meanwhile, in Romania itself there were several thousand Romanian refugees from Austria-Hungary who immediately signed up for service in the Romanian Armed Forces.
In Russia, Romanian captives complained about being worse off than prisoners of other Austro-Hungarian ethnicities, a matter which may have contributed to their decision of volunteering into Romanian service. Russian authorities were undecided about letting them join, and initially prohibited such initiatives; those who insisted to establish contact with Romania were arrested by the Russian police forces. During the same year, after consultations with Romania, the Russian executive reverted such policies. It was decided that Russia would free at most 15,000 of this demographic group, transferring them to Romania in exchange for a similar number of non-Romanian prisoners from Romanian camps.
Subsequently, those who chose to enlist were together relocated at the special camp in Darnytsia—a suburb of Kiev, rendered in Romanian as Darnița. In December 1916, that facility held some 200 officers and 1,200 non-commissioned officers, who formed the nucleus (and general command) of a "Romanian Corps". Elected First Senior of the Camp, the 40-year-old Victor Deleu was a legal professional, rank-and-file member of the Romanian National Party (PNR) and journalist from Transylvania, who came to Darnytsia after internment in Kineshma. The other members of Darnytsia camp's leadership body were Pompiliu Nistor, Vasile Chiroiu, Emil Isopescu, Valeriu Milovan, Octavian Vasu and Ioan Vescan.
Regardless of such initiatives, Romania tended to give little attention to the potential of recruitment in Russia, as many decision-makers were still uncertain about the devotion of Transylvanians and Bukovinians, and worried that they might be welcoming Austro-Hungarian spies into army ranks. Additionally, probably half of the 120,000 men excluded themselves from the pool of recruits, as Austrian loyalists, invalids or men who had reason to fear Austria-Hungary's retaliation. Support from within Romania was therefore weak, and Russian obstruction still had a part to play, but in January the camp was visited by Lieutenant Colonel Constantin Gh. Pietraru of the Romanian Land Forces, on a mission to evaluate the recruitment project. The reversal of fortunes on the Romanian front had brought a Central Powers' invasion into southern Romania, and the Romanian military authority became pressured into finding new soldiers for the defensive action.