The Spanish Civil War was an ideological and political armed conflict that took place in Spain from July 18, 1936, to March 31, 1939. The contenders were the German-backed Nationalists, composed of right and center-right groups, most of them represented by about 60% of Spanish Army officers and conservative upper classes, on one side, and the Soviet-backed socialist government of the Second Spanish Republic, supported by communist and anarchist elements, on the other side. The Spanish Civil War was a long and vicious conflict as Spain became an ideological battlefield and the warlike laboratory in which Germany and the Soviet Union would test their new weapons. In this armed struggle, right-wing groups were called Nationalists, many of whom wanted the return of the monarchy, while the leftist elements were called Republicans.
The root cause of the Spanish Civil War goes back to April 1931, when the Second Spanish Republic was proclaimed, with Niceto Alcala Zamora as its first president, forcing the Spanish king Alfonso XIII to run into exile in Paris. Despite its name, the new government was supported by extreme leftist elements, such as communist and anarchist groups, which were the results of the ideological influence of socialist and Marxist ideas the throve in European labor union organizations and university centers after the Russian Revolution. Thus, this new Republican government would often turn a blind eye when youth anarchist organizations carried out attacks against the Catholic church, setting fire to monasteries, Christian temples, and killing priests. Conservative newspapers, businessmen, and opposition politicians were also targets of these attacks.
Since the ruling Republican-Socialist coalition had failed and got dissolved after two years of government, in 1933 there was another general election, which was won by the Spanish Confederation of Autonomous Right, under Jose Maria Gil Robles, who organized a coalition government with a center-left political group. However, when the right-wing ministers were sworn in in office, the socialists, who had come out third in that election, orchestrated a general workers strike and a violent revolt in northern Spain against the new elected, right-oriented government. Although the rebellion was put down, it weakened the new government, pushing politicians and army generals on both sides of the political spectrum to opposing ideological extremes. In the 1936’s election, however, the socialists would win again, but by a slight difference, forming a new coalition government with anarchist and communist support as violence broke out throughout Spain between leftist and rightist groups.
The spark that triggered the Spanish Civil War was the assassination of Jose Calvo Sotelo, the head of the conservative opposition party on July 13, 1936. As right-wing army generals put the blame on the Republican government for the assassination, on July 18, General Francisco Franco, commander of the Spanish Army garrison in Morocco rose up in arms against the Socialist government. As many army commanders joined the rebellion, Franco and the men under his command were shipped by airplane to Spain. Supported by the German Condor Legion and the Italian Corps of volunteer units, the Nationalists would soon gain the upperhand in the conflict. Germany provided the rightist rebels with faster planes and more advance tanks than the Soviet ones fielded by the Republican Army, which was reinforced by the International Brigades.
Madrid, the capital of Spain and the seat of the Republican goverment, was one of the main targets of the Nationalist offensive, forcing the president of the Republic to move to Barcelona, Catalonia; this city was attacked in early November 1936, resulting in the Battle and Siege of Madrid, which would last until the end of the war. After almost three years of ferocious fighting, Barcelona fell to the Nationalists on January 26, 1939, and by February 5, the Republican government authorities had escaped into France. Madrid would finally capitulate in March. By that time, the British, French and American governments had already recognized General Francisco Franco as the facto President of Spain. The fiercest military encounters of this war were the Battle of Brunete, Battle of the Ebro, and the Catalonia offensive.