
Robertson presented it in San Francisco in 1915 in a paper entitled Social structure of, and ideas of law among early Philippine peoples, in a recently discovered pre-Hispanic criminal code of the Philippine Islands. It first gained scholarly acceptance when Marco donated five manuscripts of the fraudulent documents to the American historian James Alexander Robertson. Other authors throughout the 20th century gave credence to the story and the code.


In 1917, the historian Jose Marco wrote about the Code of Kalantiaw in his book Historia Prehispana de Filipinas ("Prehispanic History of the Philippines") where he moved the location of the Code's origin from Negros to the Panay province of Aklan because he suspected that it may be related to the Ati-atihan festival. A woman at the Kalibo Ati-Atihan Festival.
