From Classic Encyclopedia 1911
RUNNING AMUCK (or more properly Amok), the native term for the homicidal mania which attacks Malays. A Malay will suddenly and apparently without reason rush into the street armed with a kris or other weapon, and slash and cut at everybody he meets till he is killed. These frenzies were formerly regarded as due to sudden insanity. It is now, however, certain that the typical amok is the result of circumstances, such as domestic jealousy or gambling losses, which render a Malay desperate and weary of his life. It is, in fact, the Malay equivalent of suicide. "The act of running amuck is probably due to causes over which the culprit has some amount of control, as the custom has now died out in the British possessions in the peninsula, the offenders probably objecting to being caught and tried in cold blood" (W. W. Skeat).
Though so intimately associated with the Malay there is some ground for believing the word to have an Indian origin, and the act is certainly far from unknown in Indian history. Some notable cases have occurred among the Rajputs. Thus, in 1634, the eldest son of the raja of Jodhpur ran amuck at the court of Shah Jahan, failing in his attack on the emperor, but killing five of his officials. During the r 8th century, again, at Hyderabad (Sind), two envoys, sent by the Jodhpur chief in regard to a quarrel between the two states, stabbed the prince and twentysix of his suite before they themselves fell.
In Malabar there were certain professional assassins known to old travellers as Amouchi or Amuco. The nearest modern equivalent to these words would seem to be the Malayalim Amarkhan, " a warrior" (from amar," fight"). The Malayalim term shaver applied to these ruffians meant literally those "who devote themselves to death." In Malabar was a custom by which the zamorin or king of Calicut had to cut his throat in public when he had reigned twelve years. In the r7th century a variation in his fate was made. He had to take his seat, after a great feast lasting twelve days, at a national assembly, surrounded by his armed suite, and it was lawful for anyone to attack him, and if he succeeded in killing him the murderer himself became zamorin (see Alex. Hamilton, "A new Account of the East Indies," in Pinkerton's Voyages and Travels, viii. 374). In 1600 thirty would-be assassins were killed in their attempts. These men were called Amar-khan, and it has been suggested that their action was "running amuck" in the true Malay sense. Another proposed derivation for amouchi is Sanskrit amokshya, " that cannot be loosed," suggesting that the murderer was bound by a vow, an explanation more than once advanced for the Malay amuck; but amokshya in such a sense is unknown in Malayalim.
See Sir F. A. Swettenham, Malay Sketches (1895); H. Clifford, Studies in Brown Humanity (1898).