Seems to be mix up of various sources, cultures, and entities completely made up for Pathfinder.
To point out a few:
Cernunnos was a celtic god.
Hors, a slavic one (though he might have been invented by Christian chroniclers). So is Svarozic.
Melek Taus is a celestial being from Yazidi religion.
There are some Chinese, Semitic (e.g. Tanit, Sandalphon, Shemhazai, Uriel), and other gods, angels, and spirits on the list.
Of the Empyreal Lords mentioned in Chronicle of the Righteous, almost all are made-up, presumably to keep them as Paizo IP.
(Svarozic and Cernunnos are the main ones that stand out as based on real-world deities, viz. Slavic & Celtic, respectively. There may have been mention of one or three others, but they are rather minor or currently inactive as Empyreal Lords, e.g. the Peacock Angel[?] & Tabris.).
However, it doesn't rule out that some of the Paizo-only Empyreal Lords may have been inspired by real-world counter-parts.
Note 1: Those mentioned in the bestiaries (which are world-neutral), e.g. Hors, Tanit, Atonga, Cernunnos, etc., are based on real-world mythology - for Bestiary 1 at least (although The Forgotten, Free Even From Memory, isn't, it seems).
Note 2: Those mentioned in The Great Beyond are mostly based on real-world angels/archangels, e.g. Uriel, Sandalphon, etc. However, it seems that Paizo has moved away from making them 'official-official'. (The Great Beyond is from the 3.5 era before Pathfinder became its own thing. I'm not sure if Heaven Unleashed makes any reference to them except for those from Chronicle of the Righteous, so that may be worth checking out.)
Note 3: There are other Empyreal Lords scattered about in various products, e.g. Maluzdeh from Distant Shores. Most of these seem to be Paizo-only, although Shemhazai is based on real-world sources (Shemyaza of Jewish & Christian folklore).
1-Chronicle of the Righteous: most are Paizo-only (invented), with Cernunnos, Svarozic & Tabris being the main exceptions (there may be a couple of others mentioned in passing).
2-Bestiary (Archon & Azata): from real-world mythologies/folklore/religions.
3-Bestiary 2 (Agathion): Paizo-only.
4-Bestiary 4 (Cernunnos, Korada, Vildeis): The first is a real-world Celtic god; the latter two are Paizo-only.
5-Bestiary 6, pending (Arshea, Black Butterfly, Ragathiel): All are Paizo-only.
6-The Great Beyond (Angel &/or Archon): mostly Judeo-Christian folklore. Those not from Heaven (e.g. the Agathion leaders from Nirvana) are mostly Paizo-only. Not all of these have been updated/brought over to Pathfinder from 3.5 officially.
7-various other Pathfinder sources: Mostly Paizo-only.
Hope that helps.