Bangle was raised in Wausau, Wisconsin, and attended the Wausau West High School. After considering becoming a Methodist minister, Bangle attended the Art Center College of Design in Pasadena, California.

Bangle began his career at Opel where he designed the interior of the Junior concept car. He later moved to Fiat where he became chief designer and was credited with the design of the angular Fiat Coupé.

When he joined BMW in 1992 , he became their first American chief of design although he had little experience designing complete cars. The first car heavily influenced by his design principles, the 1999 Z9 concept car, marked a controversial departure from BMW's traditional conservative style. BMW's production vehicles incorporating Bangle's styling themes have been similarly controversial, but they have sold well.

In 2004, Bangle became the Chief of Design for the overall BMW Group, including Mini and Rolls Royce. He was replaced as Chief Designer of BMW by Dutch protégé Adrian van Hooydonk.