On This Day In History was a feature on the BBC Radio 1 breakfast show in the UK between 1988 and 1993.
As a quirk, he would often add a mildly cynical punchline to each of the stories he recounted, and then would get his "crew" (female co-host, newsreader and producer) each to guess the age of living celebrities who were born on that day.
A tie-in book of the same title was published in later years, with much advertisement by the BBC, initially just to give away on the show to a daily winner who rang in with the correct answer to a question posed by Mayo about a specific person or event of relevance to that date.
The feature ended when Mayo left the breakfast show, although when he switched to the mid-morning programme, he revived it in part with a spot called Dead Or Alive?, where he would ask listeners whether celebrities or known figures born on the date in question were still living or not.
The last fact is nearly always music related and directly links into the next song played on the show.