Several years before Universal put this movie together, it had a bigger-budget version planned with Tony Curtis and Dean Martin as the Geste brothers and Charlton Heston as Sgt.Markov. That version was not made. Heston turned down the offer and was fairly derisive about it in his book, "The Actor's Life" - an attitude shared by most critics when the film finally appeared.
There are no female speaking parts in this movie.
When Universal intended making a large-scale production, it had planned to use an all-star British cast--Richard Burton, Peter O'Toole and Albert Finney. It was eventually deemed to be too expensive so instead was filmed on the Universal back lot.
Two of the film's co-stars, Michael Constantine and Malachi Throne, would a decade later each play a villain on Electra Woman and Dyna Girl (1976), those characters respectively being The Sorceror and Ali Baba.