(Rue Montagne aux Herbes Potagères 7)
À la Mort Subite is a café that has become a city institution because it has retained its décor and furnishings from the turn of the 20th century. Ownership remains in the hands of a family originating from rue Haute, who make their own beer called Mort Subite in a brewery on rue des Capucins. The café moved to its current location in 1926 from rue de la Montagne, where it was known as La Cour Royale.
Several versions exist as to the origin of the name; most especially, that journalists, who played a game of dice here ( pitchesbak) in which losers paid the round, would often make a "sudden departure" (mort subite) ostensibly to meet a deadline and were admonished: "Don't take off suddenly if you see that you are going to lose."
Historical Dictionary of Brussels. Paul F. State.