The Title of ''Ktetor'', was one used in The Byzantine Empire – as wells as The Kingdoms of Georgia and Romania. It was common from the 13th thru 15th Centuries AD. The duties of The Ktetor was that given to a wealthy Patron who consistently provided funding to The Church for projects. This could be the building of Monasteries, Churches etc.
In most cases, The Kteror was a Title which identified the Person. As such, His standing with a Region was greatly increased. Often, local Royalty bestowed gifts and other Titles. While one would assume The Ktetor did so out of his religious beliefs or ''sense of Community'', He most often did so to curry favor or achieve power. Several Ktetor's in a Regions (if Allied), might even influence Royal Edict.
The Title would disappear by and large after the 16th Century AD.