[4] The party was established by Abdul Fattah Ismail in 1978 following a unification process of a number of Yemeni revolutionary groups in both South and North Yemen.

[6] In the first parliamentary elections in unified Yemen in 1993, the YSP won 56 of the 301 seats, finishing third behind the General People's Congress (GPC) and al-Islah.

[7] Following the 1994 civil war the party's infrastructure and resources were confiscated by the GPC government and its cadres and members were regularly subjected to unwarranted arrests and torture.

[9] Following the outbreak of the Yemeni Civil War, the party split into two factions; one remained in Yemen and labelled itself the "YSP – Anti-Aggression" and declared its loyalty to the Houthi movement and its leader Abd al-Malik al-Houthi, while much of the party's leadership, including Abdulrahman al-Saqqaf and Yasin Said Numan, went into exile in Riyadh and backed the government of Abdrabbuh Mansur Hadi.

After the split, the "Anti-Aggression" faction issued statements that they consider the leadership in Riyadh to have been expelled from the party for of their support of the Saudi-led intervention in Yemen, calling for their punishment as a result.

[16] In 2018, they condemned the STC takeover of Aden and affirmed their support for Hadi's government, calling on Saudi Arabia to intervene in order to reverse the situation.