2540

June

 * 21 - Bernice Summerfield was born on Earth colony Beta Caprisis. (PROSE: Just War)

Unknown dates

 * The Third Doctor and Jo Grant prevented the Master from fomenting war between the Earth Empire and the Draconian Empire. (PROSE: Doctor Who and the Space War) They defeated the Daleks' invasion plans on Spiridon. (TV: Planet of the Daleks) However, the path to the Second Dalek War was already set.

Behind the scenes

 * 22.09.72.2540 is given as the time the Earth cargo ship C982 jumps into hyperspace at the beginning of TV: Frontier in Space and the Doctor tells Jo Grant that they are in the 26th century. 2540 is explicitly cited as the year in the novelisation and PROSE: Shadowmind. TV: Planet of the Daleks follows some time close to this point.
 * PROSE: Just War indicates that 25th century dates given in previous books for Bernice Summerfield's life were actually part of one of the other calendar systems in use in the Mutter's Spiral of her time. In another system, she was born in 2422. (PROSE: Falls the Shadow).