Duke Henry, therefore, profited most by the Italian campaign, and this excited the jealousy of Ludolf and Konrad, who began to conspire both against him, and against Otto's authority. The trouble increased until it became an open rebellion, which convulsed Germany for nearly four years. If Otto had been personally popular, it might have been soon suppressed; but the petty princes and the people inclined to one side or the other, according to the prospects of success, and the Empire, finally, seemed on the point of falling to pieces. In this crisis, there came what appeared to be a new misfortune, but which, most unexpectedly, put an end to the wasting strife. The Hungarians again broke into Germany, and Ludolf and Konrad granted them permission to pass through their territory to reach and ravage their father's lands. This alliance with an hereditary and barbarous enemy turned the whole people to Otto's side; the long rebellion came rapidly to an end, and all troubles were settled by a Diet held at the close of 954. The next year the Hungarians came again in greater numbers than ever, and, crossing Bavaria, laid siege to Augsburg. But Otto now marched against them with all the military strength of Germany, and on the 10th of August, 955, met them in battle. Konrad of Lorraine led the attack and decided the fate of the day, but, in the moment of victory, having lifted his visor to breathe more freely, a Hungarian arrow pierced his neck and he fell dead. Nearly all the enemy were slaughtered or drowned in the river Lech. Only a few scattered fugitives returned to Hungary to tell the tale, and from that day no new invasion was ever undertaken against Germany. On the contrary, the Bavarians pressed eastward and spread themselves along the Danube and among the Styrian Alps, while the Bohemians took possession of Moravia, so that the boundary lines between the three races then became very nearly what they are at the present day. Soon afterwards, Otto lost his brother Henry of Bavaria, and, two years later, his son Ludolf, who died in Italy, while endeavoring to make himself king of the Lombards. A new disturbance in Saxony was suppressed, and with it there was an end of civil war in Germany, during Otto's reign. We have already stated that he was proud and ambitious: the crown of a "Roman Emperor," which still seemed the highest title on earth, had probably always hovered before his mind, and now the opportunity of attaining it came. The Pope, John XII., a boy of seventeen, who found himself in danger of being driven from Rome by Berengar, the Lombard, sent a pressing call for help to Otto, who entered upon his second journey to Italy in 961. [Sidenote: 962. OTTO'S CORONATION IN ROME.]