Communist Party of Spain (PCE)  Communist Party of Spain (PCE), 
Spanish Partido Comunista de España ,  Spanish political party
founded in 1921 by dissident members of the Spanish Socialist
Workers’ Party (PSOE).  In April 1920 youth members of the PSOE
split from the party, and the following year the PCE was formed
when these former socialists united with the Spanish Communist
Workers’ Party. The PCE’s first national meeting was held in
1922, but, repressed by Spanish dictator Miguel Primo de Rivera,
the party was forced to operate clandestinely. The PCE gained
strength in the early 1930s. It captured 17 legislative seats in
1936, during the polarization of Spanish politics that preceded
the Spanish Civil War (1936–39). With the outbreak of civil war,
the PCE grew rapidly, expanding from fewer than 1,000 members in
1929 and some 30,000 in 1936 to nearly 1,000,000 in 1937. As
part of the Republican front against General Francisco Franco’s
Nationalist forces, the PCE became the best-organized, most
tightly dis