Note: The following is taken from the full credits list for this entry on IMDB. As it is a website with user-submitted information, some of the data listed here, including character names may be inaccurate.
The Mummy was filmed at the Universal Studios lot between September and November of 1932. Exterior Egyptian sequences were filmed at Red Rock Canyon State Park and the Mojave Desert in California.
Scenes involving the Saxon warrior were deleted from the final cut of the film.
Leyland Hodgson, Eddie Kane, Tony Marlow, C. Montague Shaw, Pat Somerset and Arthur Tovey were all uncredited for their participation in this film.
The makeup applications used to transform actor Boris Karloff into the aged mummy Imhotep was a painstaking and uncomfortable ordeal for Karloff. He has been quoted as saying that the application and removal of the makeup was "the most trying ordeal I [had] ever endured". 
Boris Karloff spends only nine-minutes onscreen in full mummy makeup. For the rest of his scenes, where he assumes the alias of Ardath Bey, he has very little makeup.
As with many of his earlier horror works, Boris Karloff was credited only as KARLOFF in the film (all capitals).
The name Imhotep is taken from a Third Dynasty Egyptian chancellor and high priest in service to the king, Djoser. Imhotep is considered to be the first architect and engineer and physician in early history.  The name Imhotep was also used for the central antagonist in the 1999 film version of The Mummy, which is regarded as a remake, but is only loosely based on the original film.