March 12 is the feast day of the following saints:
Almut of Wetter
Alphege of Winchester
Angela Salawa
Basilissa of Asia
Beatrix of Engelport
Bernard of Carinola
Dionysius the Carthusian
Dorotheus of Nicomedia
Egdunus
Gorgonios of Nicomedia
Heiu of Hartlepool
Hieronymus Gherarducci
Joseph Tshang-ta-Pong
Justina Francucci Bezzoli
Luigi Orione
Martin-Luc Huin
Maximilian of Thebeste
Mura McFeredach
Paul Aurelian
Peter of Nicomedia
Peter the Deacon
Pionius of Smyrna
Rusticus of Vallombrosa
Seraphina
Simeon the Theologian
Theophanes the Chronographer
Vindician
12 March 1622 by Pope Gregory XV
The feast of Saint David of Wales is on March 1st. Since neither his date of birth or date of death is known, it is not possible to link March 1 with his birthday.
Yes, her feast day is March 12
She became a saint the moment she died. However, she was canonized on March 12, 1622, by Pope Gregory XV.
We know very little about Joseph, including his dates of birth and death. March 19 is probably not his birthday.
Francis Xavier was canonized on March 12, 1622, by Pope Gregory XV.
Saint Teresa of Avila was canonized by Pope Gregory XV on March 12, 1622.
St. Philip was canonized as a saint by the Catholic Church on March 12, 1622 by Pope Gregory XV.
With the majority of saints, particularly very ancient saints, there is no record of the birth dates. The only date that is recorded is the feast day of the saint which maybe the anniversary of the death of the person when the person was reborn into heaven. Therefore, this question can not be answered. Saint Patrick's feast day is March 17 but his date of birth is not known. Some say he passed away on March 17 but that is speculation as there is no factual source.
March 17 is the feast day of Saint Patrick.
Saint Thompson's birth name is Saint Matthew Thompson.
Saint Adeogba's birth name is Saint Ademayomi Adeogba.