After the marriage of his daughter Helena to Constantine he was first proclaimed basileopator ("father of the emperor") in 919 and soon after, crowned colleague of his son-in-law. His reign was uneventful, except for an attempt to check the accumulation of landed property. It was terminated by his own sons, Stephen and Constantine, who in 944 carried him off to the island of Prote and compelled him to become a monk. Instead of taking power for themselves, his sons then recognized Constantine VII as sole emperor. Romanus died in 948.
Based on an entry from the 1911 Encyclopedia Britannica.