After a tour of the Empire, Heraclius returned the cross to Jerusalem on March 21, 629 or 630. For Christians of Western Medieval Europe, Heraclius was the first crusader. The iconography of the emperor appeared in the sanctuary at Mont Saint-Michel (ca. 1060), and then it became popular, especially in France, the Italian Peninsula, and the Holy Roman Empire. The story was included in the Golden Legend, the famous 13th-century compendium of hagiography, and he is sometimes shown in art, as in The History of the True Cross sequence of frescoes painted by Piero della Francesca in Arezzo, and a similar sequence on a small altarpiece by Adam Elsheimer (Städel, Frankfurt). Both of these show scenes of Heraclius and Constantine I's mother Saint Helena, traditionally responsible for the excavation of the cross. The scene usually shown is Heraclius carrying the cross; according to the Golden Legend, he insisted on doing this as he entered Jerusalem, against the advice of the Patriarch. At first, when he was on horseback (shown above), the burden was too heavy, but after he dismounted and removed his crown it became miraculously light, and the barred city gate opened of its own accord.