During the years of 1936-1939 the Spanish Civil War took place. This was due to an imbalance between the Republicans and Nationalists.
The Republicans, led by General Azana, were based in Seville, Cadiz, Burgos and Saragossa. They recieved help from Stalin’s Russia but their military strength was dwarfed by the Nationalists.
The Nationalists were led by Generals Sanjarjo and Franc. They had the full support of both Hitler’s Germany and Mussolini’s Italy, making them a formidable enemy. They were much more professional and regimented.
Due to the fact that the Nationalists had the upper hand, they quickly began to control large areas of Spain. They held the advantage for 1936 and some of ’37, however, the massively important Battle of Guadalajara was won by the Republicans. It shifted the balance and showed the Republicans could pull on top even with inferior military strength.
In 1938 it all flipped back the other way. The Nationalists held a strong lead, pulling a victory in Catalonia.
The Spanish Civil War was majorly important because it occured just prior to World War Two, the largest war in history. It is thought that there were upwards of 1 million casualties in the Spanish Civil War. It was unfortunately a rather one sided conflict from the beginning but remains one of the largest and most brutal civil wars in history.