I got the impression the League of Seven formed as a unified defense, then after the war was reformed as the Council of Seven, with cooperation between the races ongoing, but shifting to rebuilding rather than military. The leaders were council members, though in the pdf were not referred to as part of a Council of Seven. They may have pre-dated the league in some form, but IMO, reforming the group as the Council of Seven after the sacrifice ritual seems more likely.
I think the Divine One ritual is a weaker form of the sacrifice (it doesn't give enough power to banish a god, but only requires one temporary death as sacrifice, rather than seven permanent ones). It is certainly divine in nature.
