Donald Ritchie alludes to Mifune and Kurosawa'so professional (and, apparently, personal) break in his review of Stuart Galbraith's The Emperor and the Wolf: The Lives and Films of Akira Kurosawa and Toshiro Mifune:
Actually, it took two years to complete the film though I'm not sure what percentage of that time was devoted to principal photography. In any case, Galbraith is probably correct about the basis of their split.Ritchie wrote:Why so mutually profitable an association came to an end long before their deaths has been a subject of speculation. Galbraith's is that for Mifune "the artistic benefits of working with Kurosawa were outweighed by the overwhelming business concerns that constantly plagued him" and that "Kurosawa felt betrayed and refused to understand how the actor could appear in inferior films."
This is correct, so far as it goes. At the same time, however, Kurosawa was famous for monopolizing those he needed and dropping those he did not.
Mifune led an expensive life and needed the money. Yet he faithfully wore his red beard (and remained otherwise jobless) for the many months it took to complete that 1965 film. Then he had to scramble to find lucrative work no matter where. Kurosawa then resented what he saw as defection.