broadcastarchive-umd:

In 1962, two years after Lucille Ball and Desi Arnaz had divorced and the final episode of The Lucy-Desi Comedy Hour aired (using the I Love Lucy format), Desilu Studios was struggling. In the spring of 1961, three Desilu-produced situation comedies were canceled – The Ann Sothern Show; Angel, a sitcom starring Marshall Thompson and French actress Annie Farge; and Guestward, Ho! starring Joanne Dru and Mark Miller. After a two-year run, the comedy series, Pete and Gladys starring Harry Morgan and Cara Williams,
was canceled in the spring of 1962. (The red-headed Williams had been
promoted as the next Lucille Ball.) At that time, Desilu was left with
only one hit series, The Untouchables.

Arnaz, as President of Desilu Studios, offered Ball an opportunity to return to television in a weekly sitcom. Ball agreed to do the show, provided it be shown on Monday nights (the night on which I Love Lucy had aired) and that she would be reunited with Vivian Vance and her writers from I Love Lucy. CBS agreed to a full season of episodes and The Lucy Show premiered on Monday night, October 1, 1962, at 8:30 p.m.

The show began with Lucille Ball as Lucy Carmichael, a widow with two children, living in the fictional city of Danfield, New York, sharing her home with divorced
friend Vivian Bagley (Vance) and her son. Although the book on which the show was based (Irene Kampen’s Life Without George)
centered on two divorcées living together in the same house raising
their children, it was decided early on that the Lucy
character should instead be a widow. The character of Vivian Bagley became television’s
first divorced woman. (Wikipedia)