Who he was
Hilarius (also spelled Hilarus) was a Sardinian and an archdeacon of Rome. As a legate of Pope St Leo the Great at the so-called Robber Synod of Ephesus in 449 he stood up for Bishop Flavian of Constantinople and had to flee for his life. He succeeded Leo in 461 and reigned a little over six years.
What he is remembered for
He carried on Leo's firm government, settling disputes among the bishops of Gaul and Spain through Roman synods; the synod of 465 is the oldest Roman synod whose records survive. In thanks for his escape at Ephesus he built an oratory to St John the Evangelist at the Lateran baptistery, and he founded other chapels, monasteries and libraries in Rome. He is little known outside histories of the early papacy.
He is honoured by the Church as Saint. Read his page in the dictionary of saints.
Sources
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