RPG Moments of Awesome 9: Runequest’s Cults
In general, early RPGs tended to treat gods as a convenient source of mojo for clerics (or as something for high level player characters to fight). There was no particular need for non-clerical characters to claim affiliation with any particular deity.
Runequest in contrast used religious affiliation to bind characters into particular social networks. Which god a character followed defined to a fair degree where they fit into society, who they got along with and who they did not, and provided them with cult-appropriate training in skills and magic. A character with no cult affiliation was at considerable disadvantage. This was part of the general pattern in Runequest for characters to exist in a specific context, rather than springing up out of nowhere like little murder hobo mushrooms.