Henry de Percy, 1st Baron Percy the commissioning of Warwolf, a giant trebuchet which flattened the curtain walls. The defenders had tried to surrender four days earlier, but had been made to wait by the king while he tried out his new toy. In September 1305 the first joint English and Scottish parliament met at Westminster to agree a constitution for the unified state, with Percy playing a leading role in the negotiations, but Robert Bruce, a leading representative of the Scots, was already conspiring to rebel. On 25 March 1306 Robert Bruce was crowned King of Scotland at Scone Abbey, upon which Edward confiscated his
King of the Romans of Swabia was crowned "Rex Romanorum" at Mainz Cathedral (as was King Rupert centuries later), but he had another coronation in Aachen after he had prevailed against his Welf rival Otto IV. At some time after the ceremony, the king would, if possible, cross the Alps, to receive coronation in Pavia or Milan with the Iron Crown of Lombardy as King of Italy. Finally, he would travel to Rome and be crowned Emperor by the Pope. Because it was rarely possible for the elected King to proceed immediately to Rome for his crowning, several years might elapse between election and