Keaton always selected Battling Butler (1926) as one of his pets (sometimes his top pet), perhaps because it was the weakest of his children. Nevertheless it made a lot of money. Slower in pacing than the other Keatons, it builds up to the expected smashing climax. […] According to Lisle Foote, audiences would have been familiar with the source of the film, a musical comedy called Battling Buttler, a Musical Knockabout in Three Rounds, which had a successful run on Broadway in 1923 with Charles Ruggles in the title role.
“I told the original story – said Keaton – that was taken from the stage show except that I had to add my own finish. I couldn’t have done the finish that was in the show, where he just finds out in the dressing room up at the Madison Square Garden that he don’t have to fight the champion and he promises the girl he’ll never fight again. And of course the girl don’t know but what he did fight.
But we knew better than to do that to a motion-picture audience. We couldn’t promise ‘em for seven reels that I was going to fight in the ring and then not fight. We knew that we had to fight. So we staged a fight in the dressing room with the guy who had just won the title in the ring – by having bad blood between the fighter and myself. And it worked out swell”.
The picture proved Keaton’s biggest success, outgrossing Douglas Fairbanks’s Black Pirate in its first week on Broadway, and encouraging Joe Schenck to give the go-ahead for Keaton’s most ambitious production, The General, with a budget set at half a million.
Kevin Brownlow, A Hard Act to Follow, from the author manuscript

For the restoration of Battling Butler thirteen elements were inspected and analyzed: eight of those – from the Cohen Film Collection and Cinémathèque Royale de Belgique – were digitized and compared. Upon inspection it was confirmed that the first generation positive print preserved by the Cinémathèque Royale de Belgique was struck from a B-negative (none US distribution) and therefore not used for reconstruction. Four elements were finally selected for restoration: the original camera negative, two positive prints (one vintage and one from 1940s) and one second generation duplicate negative, all preserved by Cohen Film Collection. The latter was used, whenever possible, to replace portions that were missing in the original negative, namely the entirety of reel 1, and portions in every reel with the exception of reel 3. Colour grading used the amber tinted vintage print as a reference: this choice was confirmed by the information reported in the middle tails of the original negative. Opening cards were re-edited to match the vintage print.