Yes, he was.
Michael Goodliffe, who played Inspector Hauser, played Chief of Staff Bill Tanner (Bond's best friend in the books) in "The Man with the Golden Gun."
Also, Joanna Pettet played Mata Bond (daughter of Sir James and Mata Hari) in the spoof film "Casino Royale." Not an official Bond entry, but she's as sexy as any Bond girl. ;-)
On Wikipedia it states that Blofeld was German and also lived in Warsaw. It also states that when Germany took over Poland he left for Turkey. This is very ironic in that in Night of the Generals the two Blofeld actors are both Germans and are in Warsaw for the movie. You Only Live Twice was released the same year as this movie, so Donald Pleasance was playing two near identical characters. Charles Gray however was a good guy in You Only Live Twice, while in Diamonds are Forever (1971) he obviously was Blofeld.
The Great Escape reunion too with Pleasance, Nigel Stock and Gordon Jackson.
"Congratulations, Major. It appears that at last you have found yourself a real war." Ben Tyreen
The Bond thing is already listed in trivia.
How very sad about Michale Goodlife anyway he played the same role Bill Tanner
as we also saw in FYEO James Villiers and of course GE and TWINE (Michael Kitchen) and now
Quantum of Solace with Rory Kinnear as BT
another reunion of actors is Omar and Tom who both were in Dr.Zhivago
which had Geoffrey Keen (Minister of Defence, Roger's last 5 films and TLD) as Dr Zhivago's mentor
Oh one other note Michale Goodlife played the Dr. in "Van Ryan's Express" with "Great Escape" vet John Leyton
If you want to play this game, you have O'Toole, Harry Andrews and Coral Browne re-united from The Ruling Class.
"If life gives you lemons, choke on 'em and die. You stupid lemon eater."
And O'Toole and Omar Sharif from 'Lawrence of Arabia'.
I started watching this on a movie channel because I noticed that two Blofelds were playing in scenes together. I stuck around to find myself thoroughly engrossed by the film.
Yeah about that first 2 times we see Ernie FRWL & TB he's a big guy (Anthony Dawson)
Then in YOLT & OHMSS he played by shorter actors Donald Pleasance & Telly Savales
Then in DAF its a taller actor again Charles Gray
They say Ernie is a master of disguise but c'mon now.
Side note on a public access show back in the 1970s hosted by ALEX BENNETT
and his wife said they were both trivia experts.
This was a call in show BTW, so I called them and asked who was the body of Blofelt in FRWL & TB at which point they say it was Sean Connery
WOW! Guess they were wrong on that one