His career in comics began in 2000, when his first comic strip, Gnom, was accepted into Smult, a magazine dedicated to promoting promising Norwegian cartoonists. Gnom quickly became popular but when Bladkompaniet ceased publication of Smult, Eriksen abandoned Gnom and began his new series, M as a guest strip in the monthly magazine Pondus. The initial of Mads, M is a semi-auto-biographical, surrealistic strip featuring himself and his girlfriend, "Madammen" (English: The Madam).
In 2002, M began daily publication in Dagbladet, initially on a "guest" basis, until the strip became a permanent fixture, causing Hägar the Horrible to be removed from the newspaper"s comics section.
Mads Eriksen currently lives in Trondheim. A self-declared geek, he is a big fan of several popular cultural phenomena, especially Star Wars.