New civs open up the requirement and use of these civs to tell their historical stories, the more civs you have the more stories you can tell and the more campaigns you can have.
I need the kingdom Armenia in order to finish my 1st Crusade campaign.
Hense why I need Armenia and Georgia added.
Each added civ requires an in deapth campaign telling of the events in their respective histories.
Georgia
Campaign:Sword of the Messiah
King David IV The Builder campaign to unify the Kingdom and defeat the Saljuk Turks ,climax at the Battle of Didgori.
Armenia
Campaign: Fight alongside their Georgian allies against the Eldiguzids (Turks) in a campaign in Anatolia that culminates in the climactic battle of Shamkor.