Things like that did happen:It is likely the mid winter date was chosen to appease those pagans who had converted.
"The Saga of Hákon the Good credits King Haakon I of Norway who ruled from 934 to 961 with the Christianization of Norway as well as rescheduling Yule to coincide with Christian celebrations held at the time. The saga says that when Haakon arrived in Norway he was a confirmed Christian, but since the land was still altogether heathen and the people retained their pagan practices, Haakon hid his Christianity to receive the help of the "great chieftains". In time, Haakon had a law passed establishing that Yule celebrations were to take place at the same time as the Christians celebrated Christmas, "and at that time everyone was to have ale for the celebration with a measure of grain, or else pay fines, and had to keep the holiday while the ale lasted.""