When was the Fatima Prayer written? The prayer said after each Decade of the Rosary.
The Decade Prayer for the rosary, commonly known as the Fatima Prayer, was revealed by Our Lady of Fatima on July 13, 1917. See:
You can learn the entire Fatima story in “The Shepherds of Fatima” by Manuel Fernando Sousa e Silva, published by Pauline Books and Media.
Fr. Vincent Serpa, O.P.