For me Civ 2 was peak Civilopedia, and Alpha Centauri was peak content-accompanying-discoveries (with the addition of quotes), but when that style got fed back into Civ 3 it lost something in translation.

I literally did not study for history from grades 6-10 because I had learned 80% of the content by reading Civilopedia entries during gameplay. It's been a huge inspiration later in life as I've thought about educational gaming -- both as a classroom teacher and now as a technologist.

PS - I still quote CEO Nwabudike Morgan and Chairman Sheng-ji Yang on a monthly basis in adult life