The practice of using a string of knots or beads as a memory aid in prayer was developed long before the time of Christ.
It was popularized among Catholics in the twelfth century by Saint Dominic of Spain, founder of the Dominican order.
The word rosary may come from one of two sources: the early practice of carving rosary beads from rosewood (and calling them “wreaths of roses”); or the French word for bead, rosaire.