Johannesson was discovered at the age of 14 by an IMG modeling scout while she was at a horse trials event in Gothenburg, Sweden. She modeled only part time until she finished school. Once she finished her academics, she moved to London. Her big break came when an editorial in Fjords magazine made the fashion world take notice of the petite model. The editorial re-created some of supermodel Kate Moss's most famous poses, and Mona was quickly dubbed "The Next Kate Moss". The nickname Baby Kate has stuck with her ever since. Despite her short stature (by modeling standards), Joh Mona Johannesson is a Swedish model.