From the martyrology:
"St Pius X, Pope, whose birthday is recorded on August 20."
Pope Pius X has a large fan club amongst traditionalists because of his tough stand on the heresy of modernism, even having a traditionalist society named after him.
Personally, I always find that rather ironic, since he was also the first of the twentieth century liturgical wreckovators, changing the order of reception of the sacraments, overturning longstanding tradition on the frequency of reception of the Eucharist, and above all fundamentally revamping the Roman Breviary.
Fortunately in the Ordinary Form, today is the feast of a rather more traditional liturgical reformer, St Gregory the Great:
"Likewise at Rome, the raising to the Sovereign Pontificate of St. Gregory the Great, an incomparable man, who, being forced to take that burden upon himself, sent forth from the more exalted throne brighter rays of sanctity upon the world."