Kammala jumla mai zuwa: Romania ta kasance mai haɗin gwiwa tare da Ƙasar Tsakiya tun 1882. Lokacin da yaƙin ya fara, duk da haka, ta bayyana tsaka-tsakinta, tana da'awar cewa tun da Austria-Hungary ta yi yaƙi da Serbia, Romania ba ta da wajibin shiga yaƙin. A ranar 4 ga Agusta 1916, Romania da Entente sun rattaba hannu kan Yarjejeniyar Siyasa da Yarjejeniyar Soja, wanda ya kafa sigogin halartar Romania a yaƙin. A cikin musayar, ya sami takunkumi na Allies don Transylvania, Banat da sauran yankuna na Austria-Hungary da za a haɗe zuwa Romania. Wannan aikin yana da babban goyon bayan jama'a. A ranar 27 ga Agusta 1916, Sojojin Romania sun kai hari kan Austria-Hungary, tare da iyakantaccen tallafin Rasha. Harin na Romanian ya fara samun nasara a Transylvania, amma harin da aka yi na Tsakiya ya kori su. A sakamakon da
Yaƙin Bucharest, Ƙungiyoyin Tsakiya sun mallaki Bucharest a ranar 6 ga Disamba, 1916. Yaƙi a Moldova ya ci gaba a cikin 1917, amma janyewar Rasha daga yaƙin a ƙarshen 1917 sakamakon Juyin Juya Halin Oktoba ya sa aka tilasta wa Romania sanya hannu kan yarjejeniyar tsagaita wuta tare da Central Powers a ranar 9 ga Disamba, 1917.