Despite its large budget, this serial utilized many sets from other Universal films, such as the laboratory and crypt set from Bride of Frankenstein (1935), the castle interiors from Dracula's Daughter (1936), the idol from The Mummy (1932) and the opera house interiors from The Phantom of the Opera (1925). In addition, the outer walls of Ming's castle were actually the cathedral walls from The Hunchback of Notre Dame (1923).
The serial was shot in six weeks with the cast and crew working many fourteen hour days.
The opening music for the episodes as well as some of the music for the action scenes are excerpts from the classical work "Symphonic Poem, Les Preludes", by Franz Liszt. In Chapter One Richard Wagner's "Good Friday Prelude" to "Parsifal" is used.
The entire four hour serial was shot in six weeks with an average of 85 set-ups a day.
King Features Syndicate released the three Flash Gordon serials to US TV in 1951. Because the television show Flash Gordon (1954), starring Steve Holland as Flash, was in syndication in late 1953, the three Universal Pictures' Flash Gordon theatrical serials were retitled for TV broadcast. Flash Gordon (1936) became "Space Soldiers", Flash Gordon's Trip to Mars (1938) became "Space Soldiers' Trip to Mars", and Flash Gordon Conquers the Universe (1940) became "Space Soldiers Conquer the Universe". To this day both the three original "Flash Gordon" serial titles and the three "Space Soldiers" titles are used.