 Mann grew up in Cheltenham, England. Mann also idolised Marco Ruas and Royce Gracie as a youngster after being introduced to the Ultimate Fighting Championship. Mann began taking Muay Thai lessons at the age of 11 and participated in jiu-jitsu and kickboxing tournaments at the age of 13. Mann competed in his first amateur fight at the age of 16 and turned professional a year later. In Japan, he fought under the name of Ronnie Ushiwaka, his mother's maiden name. (His Mothers Maiden Name was Promlert ( THAI) Mann's professional mixed martial arts career began in November 2003 with a win over Andy Dicks. A few months later, Mann made his Shooto debut, at Shooto Holland where he won via triangle choke after 56 seconds. Staying in Holland, Mann won a further fight, knocking his opponent out in under two minutes. Mann then recorded five successive submission victories.
