1996
Persona 1 or Revelations: Persona comes out for the PS1 and starts the persona series. Persona 1 is totally different from modern persona.
1999
Persona 2: Innocent Sin comes out (PS1). People liked the first one so they made another one.
2000
Persona 2: Eternal Punishment comes out (PS1) (persona 2 part 2) and nobody played it which is sad because i hear it has a really good story.
2006
Persona 3 comes out for the PS2. This time they totally change the games' identity into a form that's similar to what it is today, people liked the new direction of the series.
2008
Persona 4 comes out for the PS2 just 2 years after persona 3 because of it's big popularity, this time people like the game even more so watch out for what comes next.
2009
Persona 3 Portable (I skipped FES just like ATLUS does) comes out for the PSP, this version adds a bunch of new things including the option to play as a girl (!!) (which adds a bunch of new things) and ATLUS treats it as the definitive version.
2012
Persona 4 Golden comes out continuing the trend of definitive versions. This one adds a bunch of QOL improvements, a new end to the game (no it doesn't???), and I am currently playing it and I like it (this was a long time ago)
2016/2017
Persona 5 came out in 2016 in Japan and 2017 in the rest of the world with a big splash (don't know why I mention this again), this was the first time that a lot of people heard about the series and that's not a bad thing since P5 is one of the most stylized and polished experiences yet.
2019/2020
Persona 5 royal comes out as the newest definitive edition, this one adds stuff similarly to P4G and I have to admit the game is a little too easy (ok bud this isn't the place for that) and I don't like the new ending as much as the original (which you can still get)