Neo-Ba'athism is a far-left variant of Ba'athism that became the state ideology of Ba'athist Syria, after the Arab Socialist Ba'ath party's Sixth National Congress in October 1963. As a result of the 1966 Syrian coup d'état launched by the neo-Ba'athist military committee led by Salah Jadid and Hafez al-Assad, Ba'ath party's Syrian regional branch was transformed into a militarist organization that became completely independent of the National Command of the original Ba'ath Party.
Neo-Ba'athism has been described as a divergence from Ba'athism proper that had gone beyond its pan-Arabist ideological basis by stressing the precedent of the military and purging the classical Ba'athist leadership of the old guard, including Michel Aflaq and Salah al-Din al-Bitar. The far-left neo-Ba'athist regime in Syria, which was influenced by various Marxist ideological schools, espoused radical leftist doctrines such as revolutionary socialism abandoned pan-Arabism, sought to strengthen ties with the Soviet Union, and came into conflict with Arab nationalists such as Nasserists and the Iraqi Ba'athists, particularly Saddamists, with whom they maintained a bitter rivalry. From their seizure of power in the Syrian Arab Republic as a result of the 1963 Syrian coup d'état, neo-Ba'athist officers purged traditional civilian elites to establish a military dictatorship operating along totalitarian lines.