The title of the leader of the Romulan Star Empire, who presides over the Senate, held by Neral during the Dominion War and seized by Shinzon in 2379.
The Praetor is the head of government of the Romulan Star Empire. The office is mentioned as early as the Original Series episode Balance of Terror, in which a Romulan commander carries out an attack on Federation outposts in the Praetor's name and privately doubts the wisdom of it.
By the time of the Deep Space Nine episode Inter Arma Enim Silent Leges the Praetor is Neral, who had been proconsul when Picard and Spock met him in Unification. The plot of that episode turns on who will sit on the Continuing Committee that advises him.
In Star Trek Nemesis Praetor Hiren and almost the whole Senate are killed by a thalaron device after refusing to back Shinzon. Shinzon then takes the title for himself and holds it until his death aboard the Scimitar.