Tiercellus was the supreme commander of the Romulan fleet in the early 23rd century. He was nicknamed the "Eagle of the Romulan Empire". By 2267, he had retired to a quiet life, and had his the point of not worrying about the words he used, but was still considered to be extremely honorable. That year during an epidemic on Romulus he encountered one of his past charges, S'Talon and one of S'Talon's centurions, S'Tarleya. Tiercellus charged her with keeping S'Talon alive.