In general, fruitcakes can include any and all of the following: candied fruit, dried fruit, fruit rind, nuts, and spices. After being slowly baked, the finished fruitcake is wrapped in cheesecloth which may soaked in brandy, bourbon, whiskey, rum or other liquor. It is  then wrapped in foil and put aside to age properly.

Fruitcakes are one of the oldest surviving traditional holiday pleasures. Although in modern times we associate fruitcake with Christmas, it has been used  in ceremonial celebrations of all kinds throughout Europe, including religious holidays, harvest celebrations, birthdays and weddings since the 1700's.

English Fruit Cake

Farmer, Fannie Merritt. 1918. The Boston Cooking School Cookbook.
 

1 lb. butter
2 tablespoons milk
1 lb. light brown sugar
3 lbs. currants
9 eggs
2 lbs. raisins, seeded and finely chopped
1 lb. flour
2 teaspoons mace
1/2 lb. almonds, blanched and shredded
2 teaspoons cinnamon
1 teaspoon soda
1 lb. citron, thinly sliced and cut in strips
 

Cream the butter, add sugar gradually, and beat thoroughly. Separate yolks from whites of eggs; beat yolks until thick and lemon-colored, whites until stiff and dry, and add to first mixture. Then add milk, fruit, nuts, and flour mixed and sifted with mace, cinnamon, and soda. Put in buttered deep pans, cover with buttered paper, steam three hours, and bake one and one half hours in a slow oven, or bake four hours in a very slow oven. Rich fruit cake is always more satisfactory when done if the cooking is accomplished by steaming.