John O'Callaghan is an Irish musician and songwriter, best known as the lead vocalist of the rock band The Maine. He has been active in the music industry since the mid-2000s and has contributed to the band's distinctive sound, which blends elements of pop rock and alternative music. In addition to his work with The Maine, O'Callaghan has collaborated with various artists and participated in numerous music festivals. His songwriting often reflects personal experiences and emotions, resonating with fans around the world.