However, a few years later the Arab conquest began and Jerusalem came under Muslim rule. Up until the 10th century, the worshipers of the True Cross continued to exist, without coming to much harm. They even increased in territories that had remained Christian, in particular, Constantinople. When difficulties arose and the Christians were persecuted, the Cross was withdrawn from its setting and hidden once again. Ninety years later (in 1099) it reappeared once more thanks to the Crusades started by the Church to liberate the Holy Land. It was reinstated with honor in the Basilica of the Holy Sepulchre. It became the symbol of the Crusader Kingdom of Jerusalem.
However, that was just for the time being, as in 1187, the True Cross disappeared once again, and this time definitively, on the battlefield of Hattin, next to Lake Tiberius in Galilee. The crusaders had taken it with them to bring victory against the Sultan Saladin. However, they lost the battle, and Jerusalem fell into the hands of the sultan. The Cross disappeared without leaving a trace. Legend has it that Pope Urban III, on hearing the news, dropped dead.