Films that have the main role feel like a supporting role

Whichever way you slice it, SEVEN SAMURAI. It's accepted that Toshiro Mifune is the star, but he's really in a supporting role. In any case, the leader of the samurai is probably the pivotal role for many people, though I still see it as a story of the four farmers, particularly the conflict between the conservative faction of Manzo (who is supported by Yohei and most of the others) and the outnumbered liberal, more honorable faction of Mosuke (supported by the courageous Rikiki and few others).

I always found it interesting that the liberal faction held true to honor, while the conservatives were found to be guilty of killing samurai on the run (particularly Manzo and Yohei), and yet the samurai treat Manzo with the utmost respect.