Draconian

Draconians were a race of reptilian humanoids from Draconia.

The Draconians were ruled by an Emperor, who depended on the great families for support. Draconian culture was male-dominated and strongly valued honor.

The Draconian Empire was already in existence by the 21st century, when the Doctor helped them fight a space plague, and was rewarded with an honorary ranking of a Draconian noble.

It is unclear which incarnation of the Doctor this was, although it was probably the Second Doctor.

In the 26th century, the expanding Draconian Empire came into contact with the Earth Empire. A misunderstanding during first contact led to the destruction of a Draconian vessel and a brief but devastating war, which ended with the signing of a peace treaty.

Twenty years later, the Master attempted to sabotage the fragile peace, but was thwarted by the Doctor and Jo Grant. (DW: Frontier in Space)