Foie gras
The technique of gavage dates as far back as 2500 BC, when the ancient Egyptians began keeping birds for food and deliberately fattened the birds through force-feeding. Today, France is by far the largest producer and consumer of foie gras, though it is produced and consumed worldwide, particularly in other European nations, the United States, and China.
Foie gras
Fattened liver can be produced by alternative methods without gavage, and this is often referred to either as "fatty goose liver" or as foie gras (outside France), though it does not conform to the French legal definition. This method involves timing the slaughter to coincide with the winter migration, when livers are naturally fattened.
The winner of the Coup de Coeur award at the Salon International d'Alimentation, SIAL 2006, Patería de Sousa produces fattened livers without force-feeding. This has only recently been produced commercially, and is a very small fraction of the market.