In the first (London) run of the play, Leo McKern played not Cromwell but the Common Man, a narrator-figure who addresses the audience and plays several characters in the story - More's servant Matthew, the man who rows him home, his jailer, etc. These characters also appear in the film, but are played by several actors. The original stage device of having them all played by the same actor was kept in the 1988 version. In the play, the lines stating what happened to the historical figures after More's death are spoken by the 'Common Man'; in the film, they are spoken in voice-over at the end by Colin Blakely, who plays Matthew.

One of only 4 productions to win both the Best Play Tony (1962) and the Best Picture Oscar (1966). The other 3 are My Fair Lady (1957/1964), The Sound of Music (1960/1965) and Amadeus (1981/1984).

The original play opened at the ANTA Playhouse (New York) on November 21, 1961 and played for 637 performances starring Paul Scofield.

The producers originally wanted Laurence Olivier as Thomas More and Alec Guinness as Wolsey, but director Fred Zinnemann insisted on Paul Scofield and Orson Welles in the roles.

The trial and execution scenes are based very closely on an eyewitness account, published anonymously in the Paris Newsletter of August 4, 1535.

To keep the budget under $2 million, all the actors took salary cuts. The only actors to receive payments over £10,000 were Orson Welles, Paul Scofield and Susannah York.

Truckloads of Styrofoam were ordered to simulate a snowy landscape. As soon as it was delivered, real snow began falling.