Quindecennalia

There is evidence, that the quindecennalia, of fifteenth anniversary of Trajan's proconsular authority, and of his adoption to the empire, was celebrated in 111, or the year after Pliny's arrival in Bithynia.

There is good literary evidence for Honorius' tricennalia in 422, which is at the end of perfect quinquennial sequence from 393, as well as consular vot xxx mvlt xxx solidi, though there do not appear to be any vota coins marking his quindecennalia or quinta quinquennalia.

On 1 January 112... the year opened with a series of celebrations to mark the quindecennalia of the emperor's ascension.