Going through the Beta Site champion pages, plus a few of harrow's post (about multi-allegiances champions and about Sion's origin) I made a list about the Factions and it's champions:
About the factions:
There are currently 12 factions, plus the Independents.
Demacia, Noxus, Zaun, Piltover, Bandle City, Bilgewater, Ionia, Freljord being the City States recognized by the league.
Mt. Targon, Shadow Isles, Shurima and The Void being places where there weren't any cities, or are another dimension or something.
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