Colt .45 and juramentados go together. The United States Army shipped Colt .45s in 1902 as the only weapon effective against the juramentados, in sum, that is, all Filipinos, who seemed really not to like people invading their lands, but kay ano bakit wherefore why?
Juramentado, popular in the lexicon of Americans in the Philippines, comes from the Spanish word juramentar, to swear. Its cute coinage, origin the Philippines, is from Spanish priests, who came up with the term in dealing with their Moro problem, the Muslim population in the south whom neither Spain nor America broke (or even the current Philippine government for that matter, but that story belongs in a different book). Juramentados were Moros sworn to kill Christians invading their Moro lands, hence, juramentados were all Muslims, according to the priests. A similar misapplication arises with the term jihadist.
The Colt .45 on the other hand was the bomb. Here is a description of the death of a Filipino in Muddy Glory: America’s Indian Wars in the Philippines:
“…he was finally felled by a .45 slug through both ears…he had thirty-two Krag balls through him and was only stopped by a Colt .45—the thirty-third bullet.”
Huzzah! Thus, the U.S. Army replaced the useless Colt .38s and shipped new Colt .45s to the Philippines in 1902. Further experiments on ‘both cadaver and livestock’ to determine the best bullet were undertaken in 1903: “It is desired that the board convene at the Springfield Armory…to draw up…a program of experiments and tests which it shall desire to make.” Well, how now the carabao! Turns out the minimum caliber acceptable on cadaver and lifestock was, of course, the .45. (Great thanks for the exacting, clinical research by John Potocki in his book The Colt M1905 Automatic Pistol! :)