The Walnut's Latin name Juglans, translates as "Jupiter's acorn" and means a nut fit for a god. Our word Walnut comes from from the Anglo-Saxon word wealh meaning foreign or alien and hnutu meaning nut. It's thought that the Romans introduced the Walnut to Britain from Gaul. In the Périgord, France, excavations have brought to light petrified shells of nuts that were roasted during the Neolithic period, more than 8000 years ago. Around 2,000 B.C. in Mesopotamia, the Chaldeans left inscriptions on clay tablets revealing the existence of walnut groves within the famed Hanging Gardens of Babylon.
The walnut appears in Greek mythology in the story of Carya, with whom the god Dionysus (the god of wine) fell in love. When she died, Dionysus transformed her into a walnut tree. The goddess Artemis carried the news to Carya's father and commanded that a temple be built in her memory. Its columns, sculpted in wood in the form of young women, were called caryatids, or nymphs of the walnut tree.
Pickled walnuts are a traditional English pickle although there is doubt as to which country first pickled walnuts. The Pickled Walnut was certainly a common delicacy in early 1800s England. Charles Dickens mentions them in his book Pickwick Papers published in 1836. Today they are a delicacy found on tables mainly at Christmas time but many recipes can be found using them, more commonly cooked in with beef dishes or served with an English blue cheese such as Stilton.
One of the oldest recipes for Pickled Walnuts comes from Iran where walnuts are picked green in mid-summer, soaked for a lunar cycle in brine from the Caspian, rinsed thoroughly, then cooked to perfect tenderness in an open vat of honey, with fresh ginger, cinnamon, cloves and nutmeg added for flavour. This mid-summer treat was eaten "hot from the pot" as a village festival finger food, and enjoyed by young and old alike.
In Armenian cuisine, walnuts are preserved in sugar syrup and eaten whole. In Italy, liqueurs called Nocino and Nocello are flavoured with walnuts, while Salsa di Noci ("Walnut Sauce") is a pasta sauce originating from Liguria.
I have found an Austrian Christmas recipe using Walnuts which is marvellous wit a glass of Sauternes:
Rumkugeln - Rum and Walnut Balls Recipe
180 g (6 oz.) ground walnuts
150 g (5 oz.) icing sugar
80 g (3 oz.) grated dark chocolate
1 egg white
1 tbsp rum
For decorating: chocolate sprinkles
Combine all the ingredients, except the chocolate sprinkles, to form a workable dough. Let rest in the refrigerator one hour. Lightly moisten your hands; form the dough into small balls and roll in the chocolate sprinkles.