No one other than Charles Spearman exerted a stronger influence on the development of factor analysis than Louis Leon Thurstone. This talk will trace events in Thurstone's life, from childhood in the U.S., then in Sweden and back again in the U.S., through his engineering degrees at Cornell, his assistantship with Thomas A. Edison, the instructorship in engineering at Minnesota, and then his becoming a psychologist by earning the Ph.D. degree at The University of Chicago. After chairing a department at Carnegie Tech, his faculty appointment at Chicago served to support his major contributions to factor analysis and quantitative psychology. I will summarize those contributions and will recall some of my personal and professional experiences with Thurstone both at Chicago and Chapel Hill.