Castellan is a rank in the Order of the Black Templars. It is the equivalent of a lieutenant for this esoteric order, standing immediately after the rank of marshal. Castelans are warriors who have proven their skill with weapons, who can feel the battle and lead their fighters to victory. In combat, they prefer close combat, using power and sawblades or bolters, and less often, melta weapons or flamethrowers.
Castellans perform tasks related to the management of the Order's combat companies and fortresses. If the Castellan serves well, he can expect to be promoted to the rank of Marshal.