In a saucepot, combine red grape juice, cranberry juice, and water.
Add sugar or any other sweetener of your choice. This step is optional and can be adjusted in the end.
Add spices, thinly sliced ginger, frozen or fresh cranberries, cinnamon sticks, cloves, star anise, orange and lemon slices. Mix well.
Heat the mixture on medium heat until it begins to simmer. Do not boil.
Reduce heat to low and simmer, covered, for 20 minutes. Check for sweetness and add a couple of tablespoons of sugar if needed, heat until it dissolves. If the flavor is too intense for you, dilute the drink with a little water or add more fruit juice.
Remove the pot from heat, strain or remove the fruits and spices with a slotted spoon, and serve warm in heatproof glasses.
To make it even more inviting and visually appealing, garnish the mulled wine with orange slices, cinnamon sticks, star anise, and a few fresh cranberries.