My game came before Persona in the timeline. I'm basically the original Persona protagonist, just sayin'.

As far as I know the persona timeline goes:

Devil Summoner (both games neutral ending) --> SMT If --> Persona (Ic Queen ending) --> Persona 2 Eternal Punishment (IS didn't happen) --> Persona 3 (True ending) --> Persona 4 --> Persona 5

Technically Ice Queen Quest and SEBEC are both canon as far as P1 goes.

Yeah, I guess that's true.

Didn't someone on Reddit make a huge chart to sort out the "timeline".

Makes about as much sense as the Zelda timeline honestly, I usually don't try and tie games together unless it's something like SMT If... with Persona.
I never played Devil Summoner, so I'm not sure how it really ties into that.

Yeah, I think so.

Devil Summoner takes place way in the beginning. All the megaten games start from there as far as I know