Rumors that 'Wonderful World of the Brothers Grimm' could never be "restored" because the original 3-panel Cinerama camera negatives were heavily water damaged are untrue. Sources close to Warner Brothers and Cinerama Inc, report there is actually very minimal water damage to one edge of one panel in only some reels, and the Technicolor color separation prints are intact for the entire film. Therefore if any of the water damage actually would show on screen or video, that footage could be replaced with new negative made from the Technicolor separations. 3 color separation reels for each of the 3 Cinerama panels means the replacement process would be costly, but not impossible.

Turner Classic Movies now shows the full-length version of this film, having added the short prologue, plus Overture, Intermission with Entr'Acte and Exit Music that were not included on the VHS or laserdisc.

The second major motion picture filmed in 3-camera Cinerama, although it was released before the first, How the West Was Won (1962).

Although Buddy Hackett sang in "The Music Man", he had what could be described as a "funny" singing voice which would have seemed out of place in the eerie "flute-playing" scenes of "The Singing Bone". So his singing was dubbed by Clinton Sundberg, the actor who played the Prime Minister in the film, and who rarely sang onscreen. Although Sundberg did not have a trained singing voice, it had the right gravitas for the somber fairy tale.

One of only two movies (the other being "How the West Was Won") filmed in the true three-screen Cinerama process. (Other Cinerama films, such as "This Is Cinerama" and "Cinerama Holiday," were more documentary-style in nature; "Brothers Grimm" and "West" told fictional stories.) Other movies such as "It's a Mad, Mad, Mad, Mad World" were touted as Cinerama, but were actually filmed in a one-camera widescreen process, such as Ultra Panavision 70, and projected on a curved Cinerama screen.

Sir Ludwig and Hans were created to somewhat resemble Don Quixote and his squire Sancho Panza.

Producer George Pal originally wanted Peter Sellers and Alec Guinness to play the Brothers Grimm, but MGM vetoed the idea.

Walter Rilla spoke English with a heavy German accent, so his voice was dubbed by another actor.

In the original version of The Singing Bone, the killer and his victim are a pair of brothers who set out to find and kill a dragon. In the movie version, they were made into a knight and his squire who fight a dragon so as to avoid having Terry-Thomas's character commit fratricide.

One of the puppets in 'The Cobbler and the Elves' sequence was "The Yawning Man" from the 1958 Pal feature "Tom Thumb".

It was originally planned that Laurence Harvey and Karl Boehm, in addition to playing the Brothers Grimm, would each play roles in all three of the Grimm fairy tales dramatized within the film. In the event, only Harvey had a secondary role, and only in the middle fairy tale shown, "The Cobbler And The Elves".