These wars brought into a community of interests the kings of the house of Árpád and the Hapsburgs, whose first great ancestor, Rudolph, ascended in 1273, the German imperial throne, the stability of which was endangered by Ottokar. The latter had seceded from the German empire, and was now building up at its expense his own great Slavic kingdom. It was quite natural, therefore, that Ladislaus IV., King of Hungary, and Rudolph of Hapsburg, should enter into an armed alliance for the purpose of combating the common enemy, who, confident in his power, threatened both his eastern and his western neighbor. Twice they led their joint armies against Ottokar, and, at last, in the course of the second campaign in 1278, they completely routed the Czech armies near Stillfried and Diernkrut in the plain of the Morava, or March. Side by side with Rudolph’s ten thousand men fought forty thousand Kun warriors against Ottokar, the preponderance of the Hungarian arms securing at last the triumph of the allies. Ottokar’s power was overthrown and he himself fell, buried beneath the ruins of his kingdom. Rudolph strengthened the German throne, whose fate the events of subsequent centuries closely identified with that of his family, and the Austrian principalities became the hereditary provinces of the Hapsburgs. Hungary derived but an unequal benefit from this triumph. To be sure the gratitude of the ally, freed from a formidable enemy, was fervent, and his vows of friendship (not always respected by his successors) most earnest. Thus Rudolph writes to Ladislaus IV.: “Tongue cannot tell, nor pen describe, the immense joy we feel at your having risen with so powerful a force to avenge our common injuries. Wherefore, glorifying God, we express the greatest gratitude of which we are capable to your Majesty, and loudly promise that no vicissitude shall shake us in the indissoluble alliance which we have vowed to you.” The booty, gratifying the avarice of a few and the vanity of the nation, could also hardly be reckoned a solid advantage. One important result accrued, undoubtedly by the triumph of the allies, also to Hungary, in the destruction of Ottokar’s Slavic kingdom. In other respects the victory proved rather a disadvantage, for, instead of strengthening the power of the state, it relieved the minds of the powerful lords in the land, who now, freed from anxiety, once more indulged their self-seeking propensities, and labored to ruin the country.