BC

BC or B.C. was an initialism (Before Christ) (PROSE: The Best of Days) used to designate an Earth year's position relative to the epoch known as AD. Sometimes BCE was used instead. (COMIC: Crossing the Rubicon) The term "BC" thus designated a negative number; 100 BC was ninety-nine years before 1 BC. Its positive counterpart was AD.

There was, however, a question as to whether the year 1 BC was followed by the year 0 or the year 1 AD. Some people, including the human chronologist Professor Wagg, clearly believed that 1 BC was followed by 0, allowing him to make the claim that the year 2000 was the first year of a new millennium, as did American journalists working for television station KKBE. (TV: Doctor Who) The Eighth Doctor concurred with this opinion. (PROSE: The Novel of the Film, AUDIO: Relative Dimensions) However, the Sixth Doctor (PROSE: Millennial Rites) and Dave Young (PROSE: Escape Velocity) both strongly argued that 1 BC was followed by 1 AD, thus making 2001 the start of the 3rd millennium.

Prehistory

 * Event One: A random quarter of the TARDIS was deleted by Tegan and Nyssa, in order to escape the explosion. (TV: Castrovalva)
 * Time unknown: The Sixth Doctor wrote "THE DOCTOR WAS HERE" on an early planet's surface. (PROSE: Gone Too Soon)
 * 449,999,997,980 BC: The Fourth Doctor and Sarah Jane used a two-person space capsule to explore the Earth, which was at the time a ball of gas. (AUDIO: Exploration Earth: The Time Machine)
 * Circa 4,700,000,000 BC: The Tenth Doctor showed Donna Noble the formation of earth, witnessing it form around a Racnoss spaceship. (TV: The Runaway Bride)
 * Circa 3,500,000,000 BC: A splinter of Scaroth of the Jagaroth lived among primitive man and helped speed up the development of human culture. (TV: City of Death)
 * Time unknown: An Ice Warrior spacecraft crashed on Earth and was buried in ice. (TV: The Ice Warriors)
 * Time unknown: The Daleks were studying the cavemen for the Dalek Project. (COMIC: The Dalek Project)
 * Time unknown: Light came to Earth to catalogue its life forms and preserved a Neanderthal who came to be known as Nimrod. (TV: Ghost Light)
 * Time unknown: The Eighth Doctor, Samson and Gemma Griffin visited prehistoric Earth. (AUDIO: Terror Firma)
 * Time unknown: The Eighth Doctor and Sam arrived at Stonehenge. (PROSE: The People's Temple)
 * Circa 100,000 BC: The First Doctor, Ian Chesterton, Barbara Wright, and Susan helped the cave-dwelling Tribe of Gum to make fire. (TV: An Unearthly Child, PROSE: The Eight Doctors) Around the same time, the Dæmons arrived on Earth and began their experiments with humanity, assisting modern humans in wiping all but a very few Neanderthals. (TV: The Dæmons)
 * Circa 59,000 BC: the Gubbage Cones were the dominant empire in the galaxy. Their empire encompassed the silicon Excalbians, the feathered people of Velopssi, androids from Exo III, the Lamp People of Badafex, Ice Warriors and Ogrons, as well as Mire Beast fighting pits. (PROSE: The Crystal Bucephalus)
 * 55,519 BC: Urbanka's ozone layer collapsed, and Monarch's ship departed on its first voyage to Earth. (TV: Four to Doomsday)
 * Circa 40,000 BC: Five Euterpians arrived on Earth in Australia and began setting up a ley line of beacons on the planet's surface which their mother ship could use as a guide to split the planet apart and harvest its core for fuel. A random solar flare destroyed the mother ship, and the Euterpian away team was trapped on Earth until the late 20th century. (PROSE: Invasion of the Cat-People)
 * 35,519 BC: Monarch's ship made its first visit to Earth. Kurkutji and several other Aborigines were kidnapped from Australia and converted into androids. (TV: Four to Doomsday)
 * Circa 33,000 BC: The Eleventh Doctor and Rory Williams visited the future site of Los Angeles, California, where the TARDIS became stuck in a tar pit. They encountered a mammoth and a sabre-toothed tiger. (COMIC: The Doctor and the Nurse)
 * 29,185 BC: The Ninth Doctor and Rose Tyler encountered a tribe of Neanderthals. (PROSE: Only Human)
 * 25,519 BC: Monarch's ship returned to Urbanka from its first visit to Earth. (TV: Four to Doomsday)
 * Circa 23,000 BC: The Tzun ventured out from S'Arl in Beta Centauri and fought a war with the Darklings of Yuggoth. (PROSE: First Frontier)
 * Circa 18,000 BC: Two Krynoid pods arrived in Antarctica and went into hibernation. (TV: The Seeds of Doom)
 * Circa 16,000 BC: A Tregannan survey team consisting of Sancreda and Scryfan visited Cornwall; Sancreda ended up abandoned and marooned there. (AUDIO: The Spectre of Lanyon Moor)
 * 15,519 BC: Monarch's ship made a second visit to Earth, this time kidnapping Princess Villagra and several other Mayans and converting them into androids. Monarch's ship returned to Urbanka. (TV: Four to Doomsday)
 * Circa 10,000 BC:
 * The Last Great Ice Age ended, and the Cold went dormant, to awaken again in early 1963. (PROSE: Time and Relative)
 * A splinter of Scaroth invented the first wheel on Earth and showed humans how to use fire, (TV: City of Death) around which point the Silents' occupation of Earth began. (TV: Day of the Moon)
 * A war erupted between the planets Hextacosulous Blue and Hextacosulous Green; it would eventually destroy them both. (PROSE: The Lampblack Wars)
 * The planet of Zolfa-Thura was reduced to a desert in a civil war, leaving only its projector screens. The lone survivor of this conflict, Meglos, went into hibernation, while the screen's power source, the Dodecahedron, transferred across space to the nearby planet of Tigella. (TV: Meglos)
 * A Cyber-ship containing Cyberman of indeterminate origin was caught in a temporal storm and crashed into the Arctic Circle, where they would remain trapped until the 21st century. (GAME: Blood of the Cybermen)
 * The ancestors of the Koyukon first settled what became known as Alaska. (AUDIO: The Land of the Dead)
 * According to one account, the Sontaran-Rutan war started circa 8395 BC. (GAME: The Gunpowder Plot)
 * Circa 6700 BC: Reyn's ship crashed in Swallow Woods. (PROSE: The Way Through the Woods)
 * Circa 6000 BC: The Thains became extinct. (PROSE: Placebo Effect)
 * 5519 BC: Monarch's ship made its third visit to Earth, this time kidnapping Lin Futu and other natives of China. (TV: Four to Doomsday)
 * Circa 5000 BC: Horus and his Osiran followers tracked Sutekh (TV: Pyramids of Mars) and his sister Nephthys (PROSE: The Sands of Time) across the galaxy to Egypt where the renegade Osirans were defeated. Sutekh was imprisoned beneath a pyramid, (TV: Pyramids of Mars) while Nephthys' mind was extracted and placed inside a canopic jar. (PROSE: The Sands of Time) Egyptian culture from this point would be based upon the Osiran pattern, (TV: Pyramids of Mars) while Wars of the Gods entered many of Earth's mythologies. (TV: Pyramids of Mars, PROSE: The Sands of Time)
 * 5000 BC: Mondas drifted away from its twin planet Earth and the solar system on a journey to the edge of space. (TV: The Tenth Planet)
 * Circa 4064 BC: The Weave ship WSS Exalted crashed to Earth after a battle with the Tahnn. The Glamour aboard extended Owain's lifespan so he could guard the Weave. (PROSE: The Glamour Chase)
 * Circa 3532 BC: Kwundaar was banished from Traken after the Source was created. (AUDIO: Primeval)
 * Circa 3500 BC: Sontaran Field Major Styx arrived in Egypt, where he was briefly worshipped as the god Sontar before being entombed. (COMIC: The Gods Walk Among Us)
 * 3300 BC: The Second Doctor visited a village near Lake Garda and met Flinthair. (PROSE: Loop the Loup)
 * 3119 BC: Iraxxa and Friday entered stasis and slept for the next 5,000 years. (TV: Empress of Mars)
 * 3019 BC: Monarch's ship returned to Urbanka from its third visit to Earth. (TV: Four to Doomsday)
 * Circa 3000 BC: According to the Eleventh Doctor, Mars was the centre of a vast empire during this time while humans were barely out of their caves. The Ice Warrior Grand Marshall Skaldak was on Earth during this time and somehow wound up frozen in the ice at the Earth's North Pole. (TV: Cold War)
 * 3000 BC: A possible date for the first divergence of the Cybermen of Mondas, a group of Cybermen known as the Faction left Mondas while the Mondans remained. (PROSE: Iceberg, TV: The Tenth Planet) The Faction headed for Planet 14, eventually developing into a separate group without connection to the Mondans. (PROSE: Iceberg)

3rd millennium B.C.

 * Circa 2700 BC:
 * A splinter of Scaroth of the Jagaroth lived among the ancient Egyptians, and helped speed up the development of human culture, including the building of the Pyramids. (TV: City of Death)
 * The First Doctor, Steven Taylor, and Sara Kingdom arrived in Egypt, were pursued by Mavic Chen and the Daleks and met the Monk. (TV: The Daleks' Master Plan)
 * The Seventh Doctor and Ace visited Mesopotamia. (PROSE: Timewyrm: Genesys)
 * Circa 2600 BC: The First Doctor, Susan, Barbara and Ian came to Egypt. Itennu tried to frame them for his murder of Menkaure, but the Doctor was able to stop him. (COMIC: The Forgotten)
 * Circa 2300 BC: A splinter of Scaroth assisted humans in making the first maps of the heavens. (TV: City of Death)
 * Circa 2200 BC: Daleks interfered in the building of the Great Pyramid of Giza in Egypt. (TV: The Daleks' Master Plan, PROSE: Dalek: The Astounding Untold History of the Greatest Enemies of the Universe)
 * Circa 2037 BC: The people of Atlantis attempted to control the Chronovore Kronos, resulting in great destruction and the mutation of one member of the court into a Minotaur. King Dalios forbade any future use of the Crystal of Kronos and it was locked away in the temple. (TV: The Time Monster)
 * Circa 2000 BC:
 * Cessair of Diplos arrived on Earth, posing as a Celtic goddess in Britain. (TV: The Stones of Blood)
 * Grave robbers stole the canopic jar containing the essence of Nephthys. (PROSE: The Sands of Time)

2nd millennium B.C.

 * 1992 BC: The Kalazian Lights were visible from the night sky of Earth. (TV: The Lost Boy)
 * 1936 BC: Emperor Rovan Cartovall mysteriously disappeared. (PROSE: The Ultimate Treasure)
 * 1911 BC: Iris Wildthyme, Edwin Turner, Jenni Marcel, and Zack Hoffman briefly visited Egypt when trying to reach London in 1911 AD. (AUDIO: Kronos Vad's History of Earth (Vol. 36,379))
 * Circa 1500 BC:
 * The Exxilons visited the planet Yemaya 4. (PROSE: SLEEPY)
 * The Tenth Doctor and June visited Greece. (PROSE: The Slitheen Excursion)
 * released Kronos and destroyed Atlantis. (TV: The Time Monster)
 * 1419 BC: Birth of Erimem, companion to the Fifth Doctor. (AUDIO: The Eye of the Scorpion)
 * Circa 1400 BC: Death of Pharaoh Amenhotep II, Erimem's father. The Fifth Doctor rescued Erimem from the resulting tumult. (AUDIO: The Eye of the Scorpion)
 * 1368 BC: On 9 July, Pharaoh Tut-Am-Tut dies. (COMIC: Dr. Who's Time Tales)
 * 1366 BC: Bernice Summerfield stopped over briefly in Egypt while eluding Robot Ants. She found a Cult of Sutekh operating at this time. (PROSE: Set Piece)
 * 1352 BC: A Vondraxian orb was found in Egypt. When the Vondrax appeared to take it back, they took the form of gods. (PROSE: Trace Memory)
 * 1334 BC: The Eleventh Doctor stopped what he described as a "weapons bearing giant alien locust attack" in ancient Egypt. He met Queen Nefertiti during this adventure. She was attracted to the Doctor, and travelled with him along with John Riddell, Amy Pond, Rory Williams, and Brian Williams, to the Silurian Ark in 2367. (TV: Dinosaurs on a Spaceship)
 * Circa 1200 BC:
 * The First Doctor, Vicki and Steven were present at the siege and fall of Troy. Vicki stayed behind under the name Cressida to marry Troilus. (TV: The Myth Makers) Some time prior to this, visited the siege, extracting chemicals from the brains of some of the humans in the camps and thus intensifying some of the conflict. (TV: The Mark of the Rani)
 * About a year later, Cressida and Troilus met the Eighth Doctor, Charley Pollard and a young William Shakespeare. (PROSE: Apocrypha Bipedium)
 * 1164 BC: Cressida was living at the Temple of Astarte in Carthage at this time. (AUDIO: Frostfire)
 * Circa 1000 BC:
 * The Exxilons visited Earth, influencing the construction of cities in Peru. It was probably some time after this that they began constructing a living city on their own world, one of the Seven Hundred Wonders of the Universe, whose absorption of all forms of energy brought about the fall of their civilisation. (TV: Death to the Daleks)
 * Horath was overthrown and the galaxy Mutter's Spiral emerged from a tyrannical age known as the Dark Empire, to which all galactic civilisations, save for the most primitive ones, were subject for an unknown amount of time. At this point in history Earth was a primitive planet and thus spared. (TV: Enemy of the Bane)
 * A Vondraxian orb was buried under the Arctic. (PROSE: Trace Memory)
 * Three members of the Gorgon race were trapped on Earth and subsequently became the subject of ancient Greek legends, particularly Medusa, who would continue to live on Earth for the next 3,000 years. (TV: Eye of the Gorgon)
 * The Fifth Doctor became the first Keeper of Traken. He defeated Kwundaar, the inventor of the Source. He gave the title to Shayla, who held it for an unknown time. (AUDIO: Primeval)
 * The Doctor traps a Threckon under the fault line of what would later become San Francisco. (PROSE: Inmate 280)

10th century B.C.

 * 905 BC: The Gryphon attacked Babylon, but was trapped by mirrors by the Eleventh Doctor and Amy Pond and deactivated by the sun. (COMIC: In the Stars)

9th century B.C.

 * Circa 800 BC: Azal sealed himself up within the Devil's Hump, awaiting the day when he should make his final judgment on humanity. (TV: The Dæmons)
 * 814 BC: Dido founded Carthage. (AUDIO: The Phoenicians)

6th century B.C.

 * 575 BC: Bigon was born in Greece, probably in Athens. (TV: Four to Doomsday)
 * 570 BC: Bernice Summerfield visited ancient Babylon. (PROSE: Walking to Babylon)
 * Circa 550 BC: A Tenctrama acting as a Sybil visited the court of King Tarquin the Proud, the last ruler of the Roman Kingdom, and offered to sell him the nine Sibylline books that foretold the future of Rome. After she burned several books when he refused, he agreed to buy the remaining three. (PROSE: Combat Magicks)
 * 519 BC: Monarch's ship visited Earth, kidnapping Bigon and several other Greeks and converting them to androids. This was the first visit during which the Urbankan met actual resistance. (TV: Four to Doomsday)
 * Circa 500 BC: A Thraal ship accidentally landed on a garden of Olabrian joy-luck crystals, leading to a war with the Olabrians and their eventual destruction. (PROSE: Ship of Fools)
 * Circa 500 BC: The Thirteenth Doctor, Graham O'Brien, Yasmin Khan and Ryan Sinclair visited Pythagoras in Crotone. (PROSE: The Pythagoras Problem)

5th century B.C.

 * Circa 450 BC: A crew of Greek sailors were taken from this time to participate in a boat race through the solar system by a group of Eternals. (TV: Enlightenment)
 * 430 BC: Bernice Summerfield and Jason Kane visited Athens and met Socrates and his student Plato. (AUDIO: The Oracle of Delphi)
 * 421 BC: The Seventh Doctor, Ace and Hector visited Athens and met Aristophanes. The war between Athens and Sparta ended in this year. (AUDIO: Mask of Tragedy)
 * 410 BC: The Eleventh Doctor, Amy Pond and Rory Williams visited Athens. (COMIC: The Chains of Olympus)
 * Circa 400 BC: The Fourth Doctor brought Leela on a visit to Athens. (PROSE: The Brain of Socrates)

4th century B.C.

 * 332 BC: Alexander the Great conquered Egypt. (PROSE: The Ruby's Curse)
 * May to June 323 BC: The First Doctor and his companions Susan Foreman, Ian Chesterton and Barbara Wright visited Babylon and met Alexander the Great, ultimately being present at his death. (AUDIO: Farewell, Great Macedon, TV: Robot) 323 BC equated to the Year of the 114th Olympiad. (AUDIO: Farewell, Great Macedon)
 * Circa 300 BC: The First Doctor, Ian and Barbara visited Alexandria during the reign of Ptolemy I. (PROSE: The Book of Shadows)

3rd century B.C.

 * 221 BC: The Eleventh Doctor and Amy Pond visited China to leave a message for River Song on a vase. (TV: The Angels Take Manhattan)
 * Circa 218 BC: The Doctor met Hannibal. (TV: Robot)
 * 210 BC: The Second Doctor, Jamie McCrimmon and Victoria Waterfield encountered Qin Shi Huang, the first Emperor of China. (AUDIO: The Emperor of Eternity)
 * Egyptian bowls dating from this century were among the artefacts abandoned by the departing colonists of the former Earth colony of Jegg-Sau in the 25th century. (AUDIO: The Relics of Jegg-Sau)

2nd century B.C.

 * 101 BC: In January, the Sixth Doctor and Evelyn Smythe visited Rome and witnessed the birth of Julius Caesar's sister Julia. (AUDIO: 100 BC)
 * 101 BC: In October, the Sixth Doctor and Evelyn Smythe visited Rome, where they met Julius Caesar's parents. (AUDIO: 100 BC)

1st century B.C.

 * 94 BC: Demetrius was born. (PROSE: The Slave War)
 * 71 BC: The Second Doctor, Ben Jackson, Polly Wright and Jamie McCrimmon encountered Spartacus during his slave revolt against the Roman Republic. (PROSE: The Slave War)
 * 55 BC: Julius Caesar led an invasion of Britain, although he claimed his purpose was reconnaissance and information gathering in preparation for a later invasion. The Eleventh Doctor, Winston Churchill and Kazran Sardick arrived during the invasion and helped defeat the Bronze God. (AUDIO: Living History)
 * On 17 December 47 BC, the Seventh Doctor and Ace visited Rome. (PROSE: The Best of Days)
 * 40 BC: The Eighth Doctor, Fitz Kreiner and Trix visited Rome, where they stopped Thorgan of the Sulumians from preventing the Treaty of Brundusium from being signed. (PROSE: The Gallifrey Chronicles)
 * Circa 40 BC: The Doctor learned swordsmanship from a captain in Cleopatra's bodyguard. (TV: The Masque of Mandragora)
 * 1 BC: The Doctor took the last room at the inn on the first Christmas. (TV: Voyage of the Damned)
 * Circa 0 BC/AD: The Eighth Doctor attended the first Christmas. (AUDIO: Relative Dimensions)

Behind the scenes
"For example: The year 100,000 TL is 29,292 A.D. (100,000 — 70,708 = 29,292). The year 70,708 TL is 1 B.C. (70,709 — 70,708 = 1 B.C.), and the year —1,000 TL is 71,709 B.C. (70,709 — (71,000) = 71,709)."
 * An inherently Christian designation, BC is not generally used in calendars of the traditionally non-Christian world. Consequently, some people use BCE (meaning "Before Common Era") for BC. CE (meaning "Common Era") as a substitute for AD. These largely cosmetic replacements are thought to avoid religious offence. However, Doctor Who fiction has typically remained loyal to the BC/AD convention. Even as late as the RTD and Moffat eras, dialogue and on-screen graphics prefer the Christian convention. (TV: The Fires of Pompeii, The Pandorica Opens, A Good Man Goes to War, The Angels Take Manhattan)
 * In the real world, there is no year zero, so therefore 1 BC is immediately followed by 1 AD. Doctor Who fiction, however, is unclear as to this point.
 * On this wiki, templates and categories, both of which use, or are used in, mathematical formulae, assume the presence of a year zero, since the fiction of the DWU allows it. Hence, we deem that the year 2000 is in the 21st century.
 * In The Doctor Who Role Playing Game, Gallifrey's TL tim scale relates to the BC/AD dating system using the following mathematic formulas
 * When TL is greater than or equal to 70,709: A.D. = TL — 70,708, TL = A.D. + 70,708
 * When TL is less than 70,709: B.C. = 70,709 — TL, TL = 70,709 — B.C.

- The Cybermen.