Place all ingredients in a crockpot. Turn heat to low and cook until warm and fragrant. About 2 hours.
Ladle into glasses or mugs and garnish as desired.
Notes
If your cranberry juice is cocktail style (i.e. sweetened) skip or reduce the honey
Mulled wine can be kept on low for 4 hours. Replenish wine and cranberry juice as needed.
To make mulled wine in a slow cooker you obviously need a crockpot! As written the recipe easily fits in a standard 4-quart crockpot. When doubling or tripling the recipe opt for a 6 to 7-quart pot.