Doctor Who Regenerations (Updated Jan 2017)

First Regeneration

Oct 29, 1966

Life force syphoned from him by the planet Mondas, forcing a regeneration from exhaustion and a loss of strength.

Second Regeneration

Nov 22, 1969

Forced to change his appearance by Time Lord court order as punishment for stealing the TARDIS and breaking the non-interference law, and eventually executed by animated scarecrows.

Third Regeneration

Jun 8, 1974

Radiation poisoning upon prolonged exposure to the Great One's highly unstable web of Metebelis crystals.

Fourth Regeneration

Mar 21, 1981

Fell to the ground from great height after battling the Master at the Pharos Project.

Fifth Regeneration

Mar 16, 1984

Contracted spectrox toxaemia on Androzani Minor. Resisted the Master's attempt to block his regeneration with the help of his departing incarnation's various companions.

Sixth Regeneration

Aug 4, 1993

Injured during an attack on the TARDIS.
Blunt head trauma while suffering from chronon energy starvation after his confrontation with the Lamprey.
Exposure to focused beams of a radiation lethal to Time Lords consequent to the Rani's attack on the TARDIS.

Seventh Regeneration

May 14, 1996

Following a non-fatal shooting, the Doctor was taken to a San Francisco hospital, where subsequent exploratory surgery with a camera accidentally clogged a vein; the anaesthetic he had been given delayed regeneration for several hours.

Eighth Regeneration

Jun 19, 2003

Died after a ship he was in crash-landed on Karn, but was temporarily resurrected to consume the Sisterhood of Karn's Elixir of Life and control his next regeneration into a "warrior" capable of fighting in the Last Great Time War.

War Doctor (Ninth Regeneration)

Jun 20, 2003

Regenerative process triggered automatically at the conclusion of the Last Great Time War; implied to be the result of old age. (Date Unknown)

Tenth Regeneration

Jun 18, 2005

Directly absorbed Time Vortex energy from the Bad Wolf to save the life of Rose Tyler, causing fatal cellular degeneration.

Eleventh Regeneration (No Doctor Change)

Dec 25, 2008

Grazed by the blast from a Dalek gun stick, causing a regeneration. However, the Doctor directed the regenerative energy to his severed hand, and thus aborted a full regeneration, healing the damage he had sustained without needing to actually change. Afterwards, Donna Noble touched the energised hand's container, and an instantaneous biological Meta Crisis was created, allowing the energy to regenerate the entire missing body of the Doctor into the Meta-Crisis Doctor.

Twelfth Regeneration

Dec 25, 2009

Intentional radiation poisoning incurred in order to save the life of Wilfred Mott

Thirteenth Regeneration (New Cycle)

Nov 24, 2013

Neared death from old age after exhausting all of his regenerations. Granted a new regeneration cycle by the Time Lords. Initially underwent an explosive "reset" that regressed his current body to a younger state. Later underwent a full regeneration inside the TARDIS.

Fourteenth Regeneration

Sep 1, 2017

Unknown causation, confirmed last season this year.
Rip Capaldi.