From May to October 1917, the Blessed Virgin Mary appeared six times to three shepherd children — Lúcia dos Santos (age 10) and her cousins Jacinta (7) and Francisco Marto (9) — in the Cova da Iria, a sheep pasture near the village of Fátima in central Portugal. The apparitions began on the thirteenth of each month and continued in the face of fierce official opposition; the children were briefly arrested and threatened with being boiled in oil.
Mary entrusted three secrets to the children. She asked for prayer, penance, and the consecration of Russia to her Immaculate Heart, foretelling that war and persecution would follow if these were ignored. She promised, eventually, the triumph of her Immaculate Heart.
On October 13, 1917, before a crowd of some 70,000 — including atheists, journalists, and government officials who had come to mock — the promised 'sign' was given. After hours of rain, the clouds parted, and the sun appeared to spin, dance, change colour, and plunge toward the earth before returning to its place. Witnesses reported their soaking clothes and the ground around them were instantly dry. The Lisbon newspaper O Século, fiercely anti-clerical, reported the event in detail the next morning.
Sts. Jacinta and Francisco Marto died in the influenza pandemic of 1919–20, as Mary had predicted. Lúcia became a Carmelite nun and lived until 2005. Francisco and Jacinta were canonized by Pope Francis at Fátima on May 13, 2017; Lúcia was declared Venerable on June 22, 2023. The Sanctuary of Fátima receives some six to eight million pilgrims each year.