Saint Castulus – ancient Western Church saint – Saint Castulus (died 286) is venerated as a martyr. According to tradition, he was the chamberlain (or officer, valet) of Emperor Diocletian and the husband of Irene of Rome, also venerated as a saint

Castulus – Wikipedia, the free encyclopedia

https://en.wikipedia.org/wiki/Castulus

Saint Castulus (died 286) is venerated as a martyr. According to tradition, he was the chamberlain (or officer, valet) of Emperor Diocletian and the husband of Irene of Rome, also venerated as a saint.[2]