Australia
History
Australia was the site of Monarch's first visit to Earth, circa 45,000 BCE. During this visit he abducted several Aborigines, including their leader Kirkiutji, whom Monarch gave an android body and promised rulership of his people when Monarch made his final visit to conquer the planet (DW:Four to Doomsday).
The Doctor is known to have paid many visits to Australia. During one in 1932, he met cricket champion Donald Bradman and took five wickets for New South Wales (DW:Four to Doomsday). On another, he met Dame Nellie Melba and learned her party trick of shattering glass with a high-pitched note (DW:The Power of Kroll). In 2017, the the Doctor and his companions Jamie McCrimmon and Victoria Waterfield arrived on an Australian beach, where they soon became embroiled in the machinations of Ramon Salamander(DW:The Enemy of the World). One of the Doctor's later companions, Tegan Jovanka, was a native of Australia, having grown up on her father's farm near Brisbane(DW: Logopolis).
Sometime between the 21st century and the time of the Fourth Great and Bountiful Human Empire, Australia was merged with its nearby neighbors to form Australasia. This entire area was depopulated by the Daleks when they attacked Earth in the year 200,100. Whether the entity known as Bad Wolf restored the population of Australasia and the rest of Earth to life, as it did to Jack Harkness, is not currently known. (DW:The Parting of the Ways).