Mr. Middlebrook, 63, will report to Rick Wagoner, chairman-CEO. The automaker is in the process of integrating its previously more autonomous European operations into a new uniform global structure. The executive move resulted in other changes in high-ranking marketing positions at the automaker.
Mark LaNeve, 45, is promoted to vice president and succeeds Mr. Middlebrook, leading North American marketing and advertising. He has been marketing general manager of Cadillac since 2001, when he returned to GM after serving as president of Volvo Cars of North America.
Jim Taylor, 47, currently vehicle line executive of Cadillac cars, will become the brand's marketing general manager, replacing Mr. LaNeve.
Mike DiGiovanni, 56, marketing general manager of Hummer, will become executive director of strategic marketing, a new position. He will lead the increased focus on intermediate to long-term strategies to support volume and market share growth.
Susan Docherty, 41, will replace Mr. DiGiovanni at Hummer. She recently completed Stanford University's Sloan master's program. Before her one-year leave, she had been Cadillac's marketing director for Escalade, Escalade EXT and Escalade ESV.