Rassilon Era

The Rassilon Era referred to that part of the timeline during which the Time Lords ruled the planet Gallifrey and observed but seldom interfered with the flow of universal history. It presumably began with the ascendancy of Rassilon, founder of Time Lord society. It ended with the transportation of Gallifrey to a pocket universe at the conclusion of the Last Great Time War.

Gallifreyan civilisation existed far in the past of the 20th century time continuum. (PROSE: Goth Opera) Due to the nature of time travel the exact relation between the Rassilon and Humanian Eras, specifically whether they ran in succession or overlapped, is uncertain, although the TARDIS' navigational system differentiated between the two. (TV: Doctor Who)

By the Gregorian calendar, the Time Lords had had ten million years of absolute power by the year 2,000,000. (TV: The Ultimate Foe) However, the Rassilon Era had run since the Dark Times. (TV: The Infinite Quest)

Timeline
In the Year Zero, Rassilon activated the Eye of Harmony. (COMIC: The Final Chapter)

In the year 10639.5, Luther attempted to erase the history of the Time Lords. (COMIC: The Final Chapter)

In the year 309906, the Second Doctor was exiled to Earth. (AUDIO: Neverland)

In the year 5725.2, the Seventh Doctor intended to return the Master's remains to Gallifrey in this year. (TV: Doctor Who)

In the 5725.3, Time Lords established the Cult of Morbius. (AUDIO: Neverland)

In the year 5892.9, the Master stole information about the Doomsday Weapon from the Matrix. (AUDIO: Neverland)

In the year 6241.1, Chancellor Goth visited Tersurus, where he found the decrepit form of the Master. (AUDIO: Neverland)

In the year 6776.7, President Romana was captured and imprisoned by the Daleks on Etra Prime. (AUDIO: Neverland)

In the year 6796.8, Romana and the Sixth Doctor repelled an invasion of Gallifrey by the Daleks. (AUDIO: Neverland)

In the year 6798.2 (Intersitital space), a Dalek fleet was caught in a temporal paradox within the Time Vortex. (AUDIO: Neverland)

In the year 6798.3, Romana led a mission into the universe of anti-time (incorrectly recorded as 6978.3). (AUDIO: Neverland)

In the year 6798.5, The Eighth Doctor foiled the incursion of the forces of anti-time, but corrupted himself into Zagreus as a result. (AUDIO: Neverland)