1900

In January 1900, during the Boer Wars, the Battle of Spion Kop was fought, with the casualties including Oliver Redfern, (TV: Human Nature) and Private Tommy Watkins. (AUDIO: Tales from the Vault)

On 17 May, the First Doctor was present at the Siege of Mafeking. (TV: The Daleks' Master Plan)

In July, Lord Salisbury was serving as the Prime Minister of the United Kingdom. He was the last Prime Minister who refused to use 10 Downing Street as his official home. He instead allowed his nephew Arthur Balfour to use it. Balfour later became Prime Minister himself. (AUDIO: Upstairs)

In December, the Second Doctor and his companions Jamie McCrimmon and Zoe Heriot met the supernatural detective Thomas Carnacki in Kent. (PROSE: Foreign Devils)

Undated events
The First Doctor and Susan visited London and fought the Soul Pirates. (PROSE: A Big Hand for the Doctor)

The First Doctor, Steven Taylor and Dodo Chaplet visited South Africa and fought Kali Carash. (AUDIO: Tales from the Vault)

Constance Bassett, the mother of Tommy Brockless, died. (TV: To the Last Man)

Pai'ngya died. (PROSE: The Book of the War)

New York City's total population was 3,427,202, 1,270,080 of whom were foreign-born. (TV: The Gathering)