Not So Long Ago was based on the popular play of the same name by Arthur Richman, which debuted on 4 May 1920 in New York. Roughly five years later, on 16 May 1925, Exhibitors Herald announced that Paramount had acquired the property, and it was set to be directed by Sidney Olcott with Betty Bronson in the starring role. Bronson was known at the time for her debut screen performance in title role of the first movie adaptation of Peter Pan (1924, see entry), which was also filmed by cinematographer James Wong Howe for Famous Players-Lasky. Not So Long Ago marked Bronson’s second feature film appearance. The same day’s Exhibitors Herald included a separate announcement revealing that Ricardo Cortez had been cast that day, and filming was scheduled to begin “within next week.” The 6 June 1925 edition of Exhibitors Herald confirmed that the film had been “placed in production,” and the 27 June 1925 Exhibitors Herald followed up with a notice that production had recently concluded. A West Coast Studio Directory in the same edition of Exhibitors Herald reported that filming took place at the Famous Players-Lasky studio on Vine Street in Hollywood, though the story of the picture occurs in New York during the 1850s.
 A listing of the film in the 22 August 1925 Exhibitors Herald noted a length of 6,849 feet, but other sources, including a review in the 8 August 1925 Motion PictureNews listed a longer length of 6,943 feet. Several contemporary news items compared Not So Long Ago to Sidney Olcott’s 1923 Marion Davies vehicle, Little Old New York (see entry), including a two-page advertisement in the 16 May 1925 Exhibitors Herald that called Not So Long Ago: “A love story of New York not so long ago, when life was gay, more picturesque, more romantic, more interesting than today. There is the same opportunity for introducing famous people and places as in ‘Little Old New York’ (also directed by Mr. Olcott). The play was written by Arthur Richman and had a most successful run at the Booth and at the Bayes theatres in New York. It has great charm, romance, humor, comedy, and lends itself to a luxurious and exceedingly interesting production. This is to be one of Sidney Olcott’s greatest pictures.” The Motion Picture News review also alluded to Little Old New York as it commented that “Mr. Olcott has an almost uncanny flair for reproducing Gotham atmosphere, whatever may be the period, with absolute fidelity and life-like appeal, and to his possession of this faculty ‘Not So Long Ago’ owes its principal charm.”