Red Emperor
The Red Emperor (AUDIO: Paper Cuts) was the Fifteenth Emperor of the Draconian Empire. (TV: Frontier in Space, PROSE: The Dark Path, The Simple Things, AUDIO: Paper Cuts)
In his youth he played games of Sazou against the Doctor. On the Doctor's orders he isolated his planet from the rest of the Draconian Empire to protect it from the space plague. On his death he summoned the Doctor to stand vigil as a noble of Draconia. (AUDIO: Paper Cuts) By some accounts, the Second Doctor was the incarnation who was associated with this Emperor. (PROSE: Doctor Who and the Space War, The Dark Path)
The Third Doctor later recalled his first meeting with the Red Emperor when he arrived on Draconia in 2540, five hundred years later in Draconian history. (TV: Frontier in Space)
When the Seventh Doctor told the leadership of the planet Tairngire of the crises he had helped the Draconians avert in the past, they contacted the Draconian Empire for confirmation. The Twenty-fourth Emperor of Draconia, Xaxil, sent back confirmation that the Doctor was made a noble of Draconia and that he had the Draconian Empire's eternal favour. (PROSE: Shadowmind)
The Tenth Doctor again brought up his title as nobleman of the Draconian Empire when the Draconian Fusek Kljuco caught him in the lie of pretending to be an Adjudicator of Earth. (COMIC: Cold Blooded War!)
The Thirteenth Doctor referred to having been made nobility by the fifteenth Emperor, in order to win favour with a Draconian on late 19th century Earth. (PROSE: The Simple Things)