Pour the cider into the crockpot. Add the brown sugar and stir until the sugar dissolves.
Add the cinnamon sticks, cloves, allspice, and sliced orange to the crockpot.
Cover and cook on low or for at least 2 hours for the flavors to cook through. Feel free to allow the apple cider to warm through on low until ready to serve.
When you're ready to serve the cider, discard the spices, cinnamon sticks, and orange slices using a small strainer to remove them.
