The actor, who also appeared in. Webjun 3, 2011 · james arness, who played marshal matt dillon on tv's gunsmoke, has died. Arness died of natural causes today at his home in los angeles, according to the los. Webjun 3, 2011 · former gunsmoke actor james arness, who played marshal matt dillon in the western tv series for 20 years, died friday from natural causes, according to his website.