August was the month that the Spanish influenza epidemic of 1918 entered a second, deadlier phase after a new strain of the virus emerged. (PROSE: Casualties of War).
The Tenth Doctor noted to Reinette that this was not a very good month in 1727, warning her to "stay indoors". (TV: The Girl in the Fireplace)
In August 1914, German troops were advancing on the Belgian town of Mons. The United Kingdom was preparing to enter World War I by defending Mons. (COMIC: The Weeping Angels of Mons)
The Seventh Doctor, Ace and Bernice Summerfield arrived in Haiti in August 1915. (PROSE: White Darkness)
In August 1969, Charles Manson's "family" killed five people in Hollywood. (PROSE: Dead Romance)
In August of 1998, the Eighth Doctor, Liv Chenka, and Helen Sinclair visited Calcot and found that it was being affected by a piece of the Doomsday Chronometer. The piece's proximity to a newly installed cellphone tower allowed calls made within the town to reach into the past to dead loved ones. The Doctor and Liv found the piece while Helen met with her brother George, who died shortly before the Doctor, Helen, and Liv left. (AUDIO: Absent Friends)