Commander Kaseth was a Romulan who commanded a D'deridex-class warbird in the late 24th century.
In 2384, Kaseth warned Vice Admiral Kathryn Janeway of the USS Dauntless against entering the Romulan Neutral Zone in pursuit of the USS Protostar, stating that doing so would be an act of war. (PRO: "Crossroads")
Kaseth proceeded to lead a team of Tal Shiar commandos to Noble Isle to capture the Protostar. Finding access to the ship's systems locked out, they attempted to capture its captain, Dal R'El, on the surface, but were foiled by the Protostar crew. (PRO: "Masquerade")
Kaseth was voiced by Kimberly Brooks.