Its from a song iKo iKo and have been iKo since 1995 Air warrior days
http://www.youtube.com/watch?v=0wNSHPQj0W8 and its about to Indian tribes fighting and the words just happened to fit the game also like burning down flags and the chiefs all dress in green and Red like your home country.
My 1st hearing of it was done by the Grateful Dead witch i have seen many times
Words:
My grandma and your grandma were Sit-tin' by the fire. - My grandma told Your grandma "I'm gonna set your flag on fire."
Talk-in' 'bout, Hey now ! Hey now ! IKO, IKO, un-day Jock-a-mo fee-no ai na-n?. - Jock-a-mo fee na-n?Look at my king all dressed in red IKO, IKO, un-day. I betcha five dollars he'll kill you dead Jock-a-mo fee na-n?
Talk-in' 'bout, Hey now ! Hey now ! IKO, IKO, un-day Jock-a-mo fee-no ai na-n?. - Jock-a-mo fee na-n?My flag boy and your flag boy were Sit-tin' by the fire. - My flag boy told Your flag boy "I'm gonna set your flag on fire."
Talk-in' 'bout, Hey now ! Hey now ! IKO, IKO, un-day Jock-a-mo fee-no ai na-n?. - Jock-a-mo fee na-n?See that guy all dressed in green ? IKO, IKO, un-day. He's not a man He's a lov-in' machine Jock-a mo fee na-n?
Talk-in' 'bout, Hey now ! Hey now ! IKO, IKO, un-day Jock-a-mo fee-no ai na-n?. - Jock-a-mo fee na-n?"Iko Iko" is a much-covered New Orleans song that tells of a parade collision between two "tribes" of Mardi Gras Indians and the traditional confrontation. The song, under the original title "Jock-A-Mo," was written in 1953 by James "Sugar Boy" Crawford in New Orleans. The story tells of a "spy boy" (i.e. a lookout for one band of Indians) encountering the "flag boy" or guidon carrier for another "tribe." He threatens to "set the flag on fire."
Crawford set phrases chanted by Mardi Gras Indians to music for the song. Crawford himself states that he has no idea what the words mean, and that he originally sang the phrase "Chock-a-mo," but the title was misheard by Chess Records and Checker Records president Leonard Chess, who misspelled it as "Jock-a-mo" for the record's release.
"Jock-a-mo" was the original version of the song "Iko Iko" recorded by The Dixie Cups in 1965. Their version came about by accident. They were in a New York City studio for a recording session when they began an impromptu version of "Iko Iko," accompanied only by drumsticks on studio ashtrays.
http://en.wikipedia.org/wiki/Iko_Iko