Tavastian uprising
Häme Insurrection is an event described in a papal letter from Pope Gregory IX to the archbishop of Uppsala dated 9 December 1237.[1]
The letter describes how the Tavastians went back to their pagan beliefs from Christianity and destroyed the Catholic Church from Häme, Finland. The letter goes into detail when describing atrocities that Tavastians have done.[1] This has been seen as papal propaganda.[2]
In the letter Pope urges Christian men to take up arms against Tavastians due this action.[1]