2157

Unknown dates

 * The 22nd century Dalek invasion of Earth began, leading to a decade of occupation. (TV: The Dalek Invasion of Earth)


 * Other sources give the beginning of the Dalek invasion as 2158.


 * Cats became extinct on Earth. (PROSE: Lucifer Rising)
 * The Seventh Doctor and Roz Forrester were stranded on the planet Mars. (PROSE: GodEngine)