The Castellan of the Cardassian Union is the head of government for the Cardassian Union. (DS9 novel: Cardassia: The Lotus Flower)

In 2376, Alon Ghemor was elected as Castellan. (DS9 novel: The Never-Ending Sacrifice)

In 2381, the Castellan was female. During the Borg invasion, Nanietta Bacco negotiated with Ambassador Elim Garak in an attempt to pursuade the Castellan to send Gul Erem's fleet to the Azure Nebula. The Castellan was known to have little interest in foreign affairs if they had no positive effect on Cardassia. (ST - Destiny novel: Mere Mortals)

Several weeks later, an individual, unhappy at the loss of the Cardassian fleet at the Azure Nebula, attempted to assassinate the Castellan. (TNG novel: Losing the Peace)

CastellansEdit

• Alon Ghemor (2376 - 2379)

Heads of Government
Interstellar States	Federation President • Klingon Chancellor • Romulan Praetor • Imperial Romulan State Empress • Cardassian Castellan • Cardassian Chief Executor • Ferengi Grand Nagus • Tzenkethi Autarch • Gorn Imperator • Breen Domo • Orion Chancellor • Tholian Ruling Conclave • Thallonian Prime Minister • Tezwan Prime Minister • Enoch President • Kropasar High Cyning • Caeliar Tanwa-Seynorral • Talarian Commander-in-Chief • Knshaya Pontifex
Federation Member States	United Earth Prime Minister • Vulcan Administrator • Vulcan First Minister • Andorian Chancellor • Alpha Centauri Governor • Bajoran First Minister • Trill President • Cestus Governor • Betazoid Governor • Denevan President • Pacifican Governor • Peliar Zel Governor • Zaldan Leader
Federation Colonies	Tarsus Governor • Alpha V Governor • Mantilles Governor • Caldos Governor
UFP Member State Polities	United States President (United Earth) • Indian Prime Minister (United Earth) • Governor of Prophet's Landing (Republic of Bajor)
Mirror Universe	Terran Emperor • Terran Consul • Klingon Regent