Complex sentence: It was the ultimate incarnation of a series of companies under the sphere of influence of Colonel Willard F. Rockwell, who had made his fortune after the invention and successful launch of a new bearing system for truck axles in 1919.
Split into simpler sentences: It was the ultimate incarnation of a series of companies under the sphere of influence of Willard Rockwell. Col. Willard F. Rockwell made his fortune after the invention and successful launch of a new bearing system for truck axles in 1919.