Er, most of the ways? All of the ways?

The Spanish Civl War began with a revolt by elements in the army. This is the defining event of the outbreak of hostilities. There is little room for ambiguity here.

After the hostilities start, there is some room for ambiguity. How much of a role the various other factions that made up the Nationalists played in encouraging the revolt is a bit less clear. For instance, the records of Archbishop Gomá--the prelate of Spain--were destroyed shortly after the war began. As such, we only have his correspondence for then on. The level of encouragement given by other factions (such as the rest of the Catholic Church in Spain, royalists, the Carlists, the Falange, corporate interests, and others) is the subject of some minor (and in my opinion, relatively unimportant) debate.

But the war started because the army revolted. Whatever other actions were taken by groups that would later make up the Republicans are dwarfed by the act of taking up arms, so far as a cause of the war goes.

As always, follow up questions by OP and others are always welcome!