Harrie Irving Hancock was an American writer and journalist born in Massachusetts in 1868. He worked for the Boston Globe and as a war correspondent in Cuba. In the early 1900s, he befriended Japanese fighter Katsukuma Higashi in New York, and together they produced two groundbreaking martial arts manuals: 'Jiu-Jitsu Combat Tricks' (1904) and 'The Complete Kano Jiu-Jitsu' (1905). Brazilian naval officers Captain Santos Porto and Lieutenant Adler de Aquino translated these texts into Portuguese, making them Brazil's first exposure to Japanese martial arts. The 1905 book contained 160 techniques and over 500 illustrations, and remains in print today through Dover Publications. His books directly influenced Mario Aleixo and other early Brazilian practitioners.