It was allegedly found by Saint Helena, the mother of Constantine I, who brought it back to Constantinople for veneration in approximately 326. From Constantinople, the True Cross was broken up, and the pieces miraculously multiplied; in the fourth century, St Cyril of Jerusalem remarked that the "whole earth is full of the relics of the Cross of Christ." So many churches claimed to possess a piece of the True Cross, that Erasmus said there was enough wood in them to build a ship. Santo Toribio de Liébana in Spain holds the biggest of these pieces and is one of the most privileged pilgrimage sites for the Catholic Church.
A piece of the True Cross was the most important relic carried by the Crusaders. It was housed in the Church of the Holy Sepulchre under the protection of the Latin Patriarch of Jerusalem, who marched with it ahead of the army before every battle. It was captured by Saladin during the Battle of Hattin in 1187.
According to one legend, the True Cross was built from the Tree of Knowledge.