During the spanish civil war, republicans fought to support a democratic government for spain while nationalists fought to support a spanish dictatorship. what effect did the spanish civil war have on the buildup to world war ii?

Other countries entered the on-going civil war and dividedly supported the republican or the nationalists. The German intervention triggered World War II when it supported the Nationalists, while France and Britain supported the Republicans.  The military interventions led the countries to war. 

Germany provided heavy military training and tactics to the Nationalists that later was formed as the Condor Legion, which led the Nationalists military. The Condor Legion experienced successive victories because of their rigorous training, however, in the end, they were defeated by Britain's army.

A. southerners underestimated republicans eagerness to end slavery.