It would seem that at the beginning of his reign, Athelstan endeavoured by a friendly alliance to bring Northumbria back to English rule. It was a favourite and wise plan of his to make alliances by marriage with foreign princes, and it shows in what esteem he was held that men of power and position were ready to unite themselves with his family. One of his sisters he married to the Emperor Otto, the restorer of the Roman Empire, and another he offered in marriage to Sitric Gale, after a friendly meeting arranged by the two kings at Tamworth on the 3rd of February in the year in which Athelstan came to the throne (925). With Sitric Athelstan made a close and, as he hoped, a lasting covenant; but alas! Sitric died hardly more than a year afterwards, and on his death Athelstan, evidently in consequence of the arrangement made between them, claimed the throne of Northumbria, where he seems to have been peacefully received by the inhabitants. He spent this year in the north in active endeavours to quell the last disaffected portions in the realm. There is no doubt that at this time Athelstan designed to unite the whole of Britain under his own sway. He at first drove Howel, King of Wales, and then Constantine, King of the Scots, from their kingdoms; but not long after, if we are to believe his admirer William of Malmesbury, moved with commiseration, he restored them to their original state, saying that “it was more glorious to make than to be a king.” However, he obliged both these princes to accept their crowns as underlords to himself, thus establishing a suzerainty over them. But his plans did not suit the turbulent Danish princes. Godfrey, brother to Sitric, was at the time of Sitric’s death reigning as King of Dublin, but on hearing of Athelstan’s succession to the sovereignty of Northumbria he came over hastily and claimed the kingdom. He was, however, a man hated both in Northumbria and in Ireland, and Athelstan was strong enough to drive him out and send him back to Dublin with his Danes in the year 927. But a more formidable foe than Godfrey was in the field. This was Olaf o’ the Sandal (called Anlaf in the English Chronicle), son of Sitric Gale, who seems to have been in Northumbria at the time, but who was expelled with his uncle Godfrey, and went back with the Danes to Dublin. Godfrey died soon after, as the Irish annals tell us, “of a grievous disease,” and for ten years Olaf nursed his wrath against Athelstan and awaited his opportunity to revenge himself upon him. He went to Athelstan’s enemy, the Scottish King, Constantine, and entered into a treaty with him, marrying his daughter; and Constantine never ceased to urge him on to war with the King of England, promising to support him in every way. Olaf remained long in Scotland, and was so much mixed up with Scottish affairs, that some Scandinavian historians call him “King of the Scots.”