Helen, more than one thought of that, I'm sure.

I have to agree with Kat. Where there was settlement, the church was there. Of course for a time there were large stretches where the whites were trappers, hunters and prospectors, but these people were as nomadic as the plains Indians. Some bought women from the Indians, but generaly the woman, after having a child, relocated with the tribe or near a fort, the man returning after sessions of trapping or other effort (Kit Carson's first wife was an Indian maid, I forget her name. He finally married the money of an old family in Taos).

As Kat said, areas with white settlers in California east through New Mexico, Texas and Louisiana all had the padres in the churches and missions, who trekked to outliers periodically.

The wild west of the gunslinger really existed in railhead towns, mining camps or trade centers where the saloons, brothels and gambling halls were located. All of these places had churches.
There was no profit in holding up a prairie dog town "out on the lone prairie," and of course, no bread for the sky pilot without parishioners.