I’m not a practitioner, but I’ve done a lot of reading on Voodoo.

African, Haitian, and New Orleans.

Often, at least in Haiti and New Orleans, Catholic saints are matched with a particular Loa (spirit, god, whatever you wanna call it)

This was due to Voodoo practitioners being killed for not being Christians in Haiti. Thus, they could worship Saint whoever visually, while still interacting with their own faith. It just traveled to the new world as people did.

The process is called Syncretism, and Voodoo is hardly the first or last instance of it happening.

As you mentioned, the church has done this too.

Easter? Eostre was a fertility deity associated with spring and rabbits.

Christmas? Yule.

It goes on.