There are two Saint Priscillas and both were first century martyrs but there is no reliable information about the birth and death dates of either saint.
Priscilla was not canonized. She was declared a saint by the early Christian community long before the canonization process was instituted in the 12th century. Today, only the pope can declare a saint.
They didn't, St. Priscilla had been recognized as a saint for a thousand years before the Church began canonizing people.
All that we know about Priscilla is that she was martyred, probably in Rome, in the first century.
Priscilla Be was born in 1957.
Priscilla Reyntiens was born in 1899.
Priscilla Herdman was born in 1948.
Priscilla Welch was born in 1944.
Priscilla Napier was born in 1908.
Priscilla Buckley was born in 1921.
Priscilla Wakefield was born in 1751.
Priscilla Rattazzi was born in 1956.
Priscilla Horton was born in 1818.