1870

1870 was the year that Charles Dickens died. He left The Mystery of Edwin Drood unfinished after planning to include the events of the Gelth invasion as a conclusion. (TV: The Unquiet Dead)

The Jameson boys encountered Zygons on Tulloch Moor. Donald disappeared, and the older brother, Robert, was found two days later, driven insane. He never spoke again. (TV: Terror of the Zygons)

The Eleventh Doctor, Amy Pond and Rory Williams encountered Kahler-Jex and Kahler-Tek in Mercy, Nevada. To avoid Tek chasing him across the universe for his war crimes, Jex killed himself. Tek became the protector of Mercy. (TV: A Town Called Mercy)

Suresh Parekh was finally able to communicate with the 'ghost' he had been seeing since 1816. He found out it was the First Doctor, who was drifting through time incorporeally after an attempt to fix his TARDIS failed. (PROSE: Indian Summer)