Charlemagne, Louis' father, had signed such unorthodox alliances before. The historian lists a number of examples. Charlemagne had supported Abdellah, an exiled Mauritanian ruler in 797. Theodor, ruler of the Huns, fled an invasion by Slavic peoples and was granted refuge by Charlemagne in 805. Eardwulf of Northumbria when deposed c. 808, was also granted refuge and promised help in recovering his throne. The 815 entries of the Royal Annals focus on the campaign for restoring Harald to his throne. "The emperor [Louis] commanded that Saxons and Obodrites should prepare for this campaign, and twice in that winter the attempt was made to cross the Elbe. But since the weather suddenly turned and made the ice on the river melt, the campaign was held up. Finally, when the winter was over, about the middle of May, the proper time to begin the march arrived. Then all Saxon counts and all troops of the Obodrites, under orders to bring help to Heriold, marched with the imperial emissary Baldrich across the River Eider into the land of the Norsemen called Silendi. From Silendi they went on and, finally, on the seventh day, pitched camp on the coast at [name missing in surviving manuscripts]. There they halted for three days. But the sons of Godofrid, who had raised against them a large army and a fleet of two hundred ships, remained on an island three miles of the shore and did not dare engage them. Therefore, after everywhere laying waste the neighboring districts and receiving hostages from the people, they returned to the emperor in Saxony, who at that time was holding the general assembly of his people at Paderborn." While the campaign resulted in the looting of some areas held by the Danes, the main objective was not achieved. Harald was among the returning troops, the Danish throne eluding him. The Royal Annals report the conclusion of the assembly. "He [Louis] settled the affairs of the Slavs and of Heriold, and, leaving Heriold behind in Saxony, returned to his palace in Frankfurt." Harald apparently continued operations against his rivals. An 817 entry of the Royal Annals reports "Because of the persistent aggression of Heriold, the sons of Godofrid, king of the Danes, also sent an embassy to the emperor [Louis], asked for peace, and promised to preserve it. This sounded more like hypocrisy than truth, so it was dismissed as empty talk