Place of Origin:
The Greld were an insectoid race of arms dealers. They had six legs and two pairs of crab-like claws, mottled dark red shells, four stalked eyes, and leathery wings. When speaking to humans, they used words in the incorrect order.
During the Millennium War, the Greld and the Euterpians used the battle shroud of the Semquess and wielded the Omnethoth to destroy an entire galaxy in order to destroy a thousand of the Mad Mind’s fleets. (The Quantum Archangel)
In 1587, the Greld attacked the Roanoke colony in Virginia and implanted mind-control devices and parts of a meta-cobalt bomb in the colonists. In 1609, the Greld used their mind-controlled humans in an attempt to destroy the Armageddon Convention, but were defeated by the First Doctor. (The Empire of Glass)
Some time before 2975, the Earth Empire destroyed the Greld homeworld, which then became the prison planet Dis. (Original Sin)