Arnthor Birgisson is an award winning Icelandic-Swedish songwriter and producer whose major breakthrough came in 1998 with 98 Degrees’ “Because of You.” He has created hits for such artists as Janet Jackson, Jennifer Lopez, Celine Dion, Enrique Iglesias, Westlife, Samantha Mumba, Leona Lewis, among others. He frequently collaborates with Ina Wroldsen and the duo scored a smash with “Strongest.” His largest hit is “Impossible” performed by singer, songwriter and “X Factor” winner James Arthur.