Harry Morgan. (Edited to add: LAT obit.)
Most of the obits I’ve seen so far reference his work on “M*A*S*H” right away, but I prefer to remember him in his other famous role.
Edited to add: As Lawrence points out in the comments, Morgan also had one heck of a film career. In that vein, I’d like to spotlight Sean O’Neal’s obit at the Onion A/V Club site.
I’ve noted that the A/V Club obits, especially those written by O’Neal, do a very good job of summarizing the accomplishments of the people they are eulogizing (especially older Hollywood figures) and explaining why their lives mattered, without snark.
He also did a lot of westerns. High Noon and Support Your Local Gunfighter both come to mind.