A flitch is the entire side of an animal or fish, or a steak cut from it.
According to Wikipedia, the custom of awarding a flitch of bacon to a married couple who swear that they have never regretted their marriage, and can prove it in 'court', is by no means unique to Dunmow (historically, at least). Wikipedia cites examples from Brittany and Vienna, as well as at least one other from England; it speculates that the custom goes back to Norman or even Saxon times.
The Dunmow Flitch is referred to in Chaucer – in a way that makes it clear that the reader would be familiar with the custom. It is also mentioned in William Langland's Piers Plowman, which dates from a similar time (the 14th century). It continued to be awarded until the middle of the 18th century, the last successful claim being made on 20 June 1751.
In 1854, William Harrison Ainsworth published a novel entitled The Flitch of Bacon (subtitled The custom of Dunmow: a tale of English home). Its central character was the landlord of the Flitch of Bacon public house, which is still in business; the main plot concerns his attempts to win the flitch, by marrying a succession of women in hopes of finding the right one.
The success of the novel led to the revival of the custom in 1855, when two flitches were donated by Ainsworth himself. The trials have been held ever since, with breaks for the two World Wars. The first ceremony after World War II was held in 1949, despite rationing. The modern trials are held every leap year, in the town of Great Dunmow – rather than the nearby village of Little Dunmow, which was the traditional location.
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