This article has content related to Cresia.

The House of Cresius (Cresian pronunciation: [kɾesʲus]) was a political dynasty and later royal house that gathered prominence under Cresius I in the region of Cresia during the early 32000s DT. The family originated in the Cresian countryside, gradually rising until they controlled a Cresian tribe. From this power base, Cresius I gradually absorbed or conquered neighboring tribes, thereafter founding the Kingdom of Cresia.

The Cresii produced 104 emperors of Cresia—from Cresius I (32192-08-078 DT – ?) to Cresian XXV (? – 34019-09-069 DT). During the reign of Cresiana IX, the kingdom was elevated to an empire after territorial expansion. They ruled the Cresian Empire from its inception until 34019, with the defeat of Cresian XXV in the siege of Cresia. The empire witnessed degrees of territorial expansion under the earlier emperors, but by the time of Cresian XXV, Cresia had shrunk considerably.

They established Cresianism as the official religion of the empire, which remains the only state to have done so. Cresianism flourished under state patronage, taking on an organization that was retained to this day.