Tradition holds that on the morning of March 6, 1836, General Santa Anna ordered his band to play a song called El Degüello during the assault on the Alamo. The song supposedly meant "throat cutting" and was played in situations where no quarter was to be given to the enemy. According to author Walter Lord, the song was "a hymn of hate and merciless death, played to spur the Mexican troops forward in their final assault on the Alamo."[34]

As in the case of many Alamo "facts," not all historians agree that El Degüello was actually played at the Alamo. Writing in 1860, early Alamo historian Rueben M. Potter contended "The guns of the fortress soon opened up on them [the Mexican soldiers], and then the bands at the South battery struck up the assassin note of degüello!"[35] But modern historians, as example by Dr. Stephen L. Hardin, omit the song from their descriptions of the battle.[36]

One possible eyewitness to the battle, Madame Candelaria, reportedly told a newspaper reporter in 1899 that she heard the call played at the battle. (See FAQ: Were There Survivors At The Alamo?) The article's author exclaimed "The degüello was sounded, and Mrs. Candelaria said that they all understood very well what it meant, and every man prepared to sell his life as dearly as possible."[37] Those who believe that Madame Candelaria was not at the Alamo place little stock in her account.

http://www.thealamo.org/asked.html

Interesting tidbit...

Reminds me of a story my 8th grade history teacher told us about. He served in Vietnam and in Korea during the Pueblo incident. He said that on certain nights on the DMZ in Korea, the Commies would play the funeral durge over loudspeakers so that the ROK and US forces could hear it. That was a guarantee that the PRK forces would come down and kill one of the Americans.

That's some strong psychological warfare. Humans tie so much emotion into songs, I think that it'd be very intimidating.

Interesting tidbit...

Reminds me of a story my 8th grade history teacher told us about. He served in Vietnam and in Korea during the Pueblo incident. He said that on certain nights on the DMZ in Korea, the Commies would play the funeral durge over loudspeakers so that the ROK and US forces could hear it. That was a guarantee that the PRK forces would come down and kill one of the Americans.

That's some strong psychological warfare. Humans tie so much emotion into songs, I think that it'd be very intimidating.
In the most recent version of the film, which may not be historically accurate, David Crockett, played by Billy Bob Thornton played the the same tune on his violin while the Mexican band played. Appearantly he was rather amused by the Mexican attempt to intimidate the defenders.

It is known that the Mexicans also flew a red flag, which was the universal sign of "no quarter". The red flag was used on pirate ships and may have been used since the times of the crusades for that purpose. It was certainly an unsettling sight for the defenders.

I think that psychological warfare has an effect on even those who recognize it for what it is and don't let it affect them directly. Simply because those men will realize that other men ARE affected by it, thus changing their situation.