The First Army was one of the major units of the Romanian military in both World War I, partaking in such operations as the Romanian offensive in Transylvania in 1916 and the Battle of Mărăşeşti in 1917, and World War II, seeing action on the Eastern Front, particularly after the 23 August 1944 Coup, when the First Army fought westwards alongside Soviet units in battles such as that of Debrecen, Budapest and going as far as Prague. Following the end of the war, the First Army was disbanded on 2 June 1947, with the units under its command being transferred to one of the four newly formed Military Regions. This reorganization process was applied to all Romanian armies.