Pagan festivals AND christianization
Christian Mythology: Revelations of Pagan Origins will be the first result.
"Pagan" AND "transformation"
The Final Pagan Generation will be the first result.
"Annual Pagan celebrations" AND "Medieval Christianity"
At the bottom of the page, I found Pagans and Christians in the Late Roman Empire.
- Using Medieval in the search allows for a specific period in time without having to know the exact dates.