Was the region subject to hangings or hard police work or taxes over 10%?
I RTO'd the region.
Then: a CW-report tells: Loyalty in the region also rose.
Then a Knights joins
Then: Daily Region report: Loyalty to your realm falls 3%.
Then twice: aid the local police in your region capturing many suspects.
somewhere in between:
I lowered the tax from 10 to 5.
other things like CW and Courtier work didn't mentioned a loyality change.