Here are a few facts I remember about the show (I haven't seen an episode in decades, but our family watched often during its first run, and I remember reading a few books about the series that were written in the later 80s):
- M*A*S*H had 3 spinoffs from the original series: - AfterMASH which lasted 2 seasons, W*A*L*T*E*R which was about Radar O'Reilly and lasted 1 single episode, and of course, what became a popular show in itself and some people don't directly associate with M*A*S*H, Trapper John MD, which ran for 7 seasons. There, Pernell Roberts plays the character supposedly played by Elliot Gould in the movie and Wayne Rogers in the series.
- Wayne Rogers (Trapper John McIntyre) left the series after 3 seasons as he and Alan Alda were supposedly going to have equal billing, but Alda proved more popular and became more central to the show. A contract dispute ensued, and Rogers left.
- McLean Stevenson wasn't thrilled with being part of an ensemble cast and wanted to try for something else where he personally might get more notoriety. With the way they decided to kill off his character of Col. Henry Blake, which wasn't part of the original script and was only made known to the cast just before the OR scene where his death was announced so their shock and emotional reactions would be genuine, that eliminated the possibility of him returning in any capacity.
- Harry Morgan had appeared on the series as another character before later being cast as Col. Potter.
- Characters played by Alda and Rogers regularly called Col. Blake "Henry", showing perhaps low respect. In contrast, Alda and Mike Farrell's characters normally always called Harry Morgan's character "Col. Potter" and only on 1 or maybe 2 occasions did Hawkeye Pierce call him "Sherman". which occurred at a deeply personal moment.
- Despite Larry Linville playing the often disliked character of Frank Burns, he supposedly had good report and relations with others in the cast once the cameras stopped rolling. On the other hand, Gary Burghoff who played Radar O' Reilly, was supposedly obnoxious and somewhat demanding at times when not actively filming.
- William Christopher who played Fr. Mulcahy was said to be much like the character he played, in his real life.
- Harry Morgan and Loretta Swit were supposedly very close friends and often sat chatting for hours when not filming.
- David Ogden Stiers who played Winchester was a classical music lover in real life. Though not classically trained, he guest conducted several symphony orchestras and founded a symphony orchestra in his home town. He came out as gay in 2009.
- The final episode of M*A*S*H (Goodbye, Farewell and Amen) remains the most watch finale of any TV series in history, and spots shown during the final episode fetched higher $$ rates than were charged for that year's Super Bowl. It remained the most watched TV broadcast in history from its airing in 1983 until 2010.