Traditionalism (Spain) in the context of Bernardo Francisco de Hoyos de Seña

The Spanish Civil War (Spanish: guerra civil española) was fought from 1936 to 1939 between the Republicans and the Nationalists. Republicans were loyal to the left-leaning Popular Front government of the Second Spanish Republic and included socialists, anarchists, communists, and separatists. The opposing Nationalists who established the Spanish State were an alliance of fascist Falangists, monarchists, conservatives, and traditionalists supported by Nazi Germany and Fascist Italy and led by a military junta among whom General Francisco Franco quickly achieved a preponderant role. Due to the international political climate at the time, the war was variously viewed as class struggle, a religious struggle, or a struggle between dictatorship and republican democracy, between revolution and counterrevolution, or between fascism and communism. The Nationalists won the war, which ended in early 1939, and ruled Spain until Franco's death in November 1975.

The war began after the partial failure of the coup d'état of July 1936 against the Popular Front government by a group of generals of the Spanish Republican Armed Forces. The Nationalist faction consisted of right-wing groups, including Christian traditionalist party CEDA, monarchists, including both the opposing Alfonsists and the religious conservative Carlists, and the Falange Española de las JONS, a fascist political party. However, rebelling units in almost all important cities did not gain control, leaving Spain militarily and politically divided. The rebellion was countered with the help of arming left-wing social movements and parties and formation of militias, what led to rapid socioeconomic and political transformation in the Republican zone, referred to as the Spanish Revolution. The Nationalist forces received munitions, soldiers, and air support from Fascist Italy and Nazi Germany while the Republican side received support from the Soviet Union and Mexico. Other countries, such as the United Kingdom, France, and the United States, continued to recognise the Republican government but followed an official policy of non-intervention. Despite this policy, tens of thousands of citizens from non-interventionist countries directly participated in the conflict, mostly in the pro-Republican International Brigades.

Carlism (Basque: Karlismo; Catalan: Carlisme; Galician: Carlismo; Spanish: Carlismo) was a Traditionalist and Legitimist political movement in Spain aimed at establishing an alternative branch of the Bourbon dynasty, one descended from Don Carlos, Count of Molina (1788–1855), on the Spanish throne.

The movement was founded as a consequence of an early 19th-century dispute over the succession of the Spanish monarchy and dissatisfaction with the Alfonsine line of the House of Bourbon, and subsequently found itself becoming a notable element of Spanish conservatism in its 19th-century struggle against liberalism, which repeatedly broke out into military conflicts known as the Carlist Wars.

Don Carlos María Isidro Benito de Borbón y Borbón-Parma (29 March 1788 – 10 March 1855) was an Infante of Spain and the second surviving son of King Charles IV of Spain and his wife, Maria Luisa of Parma. He claimed the throne of Spain after the death of his older brother King Ferdinand VII in 1833. His claim was contested by liberal forces loyal to the dead king's infant daughter, resulting in the First Carlist War (1833–1840). Don Carlos had support from the Basque provinces and much of Catalonia, but lost the war. His heirs continued the traditionalist cause, fought two more Carlist wars and were active into the mid-20th century, but never gained the throne.