I think the spaghetti westerns moved Clint Eastwood from tv star to film actor.
It took a lot longer for him to be regarded as a major star. A number of factors could be regarded as important to Clint's development. The Don Siegel movies, his longevity in terms of acting career, a smart production deal for all his movies under Malpaso banner and a serious lack of competition in terms of other actors for the type of movies he was making or getting the opportunity
to make.
