Bowles comes from the Philadelphia Eagles, where he was the defensive backs coach until Juan Castillo was fired midseason. He then became the defensive coordinator with mixed results, as the Eagles defense finished 15th in total defense.
In Philadelphia, Bowles coached the 4-3 system, which doesn't match the 3-4 run in Arizona. Considering the personnel already in place, it would be tough for the Cardinals to change their philosophy, so look for Bowles to adapt.
Bowles has large shoes to fill with Ray Horton leaving the organization. Horton was believed by many to be a prime head coaching candidate in Arizona and around the league, but nothing materialized.