Guldreasi

The Guldreasi were a race that attempted to make Earth a slave planet for its war machine.

History
In the 22nd century, the Guldreasi contacted Susan Campbell to attempt to gain the human race's trust with peace treaty. The negotations failed when the Guldreasi detected the Doctor's TARDIS in London, believing it to be a trap. The Eighth Doctor revealed the Guldreasi's plans to make humans a slave race and the Earth Council banished the Guldreasi from Earth. (BFA: An Earthly Child)