The fact Quirinus has his own Flamen implies, to me, that originally this was a very important god. As the topic description states, Quirinus was of Sabine origin, and later incorporated into the Roman pantheon.

Now, what I would like to ask from you, O people far more knowledgeable, is this: what was the relationship between Quirinus and (perhaps later added) Mars like? Both seem to share many functions. From what I've understood, in late republic and the empire, the worship of Mars outnumbered that of the old Quirinus in a major scale. Was Quirinus always the less important god?