Usurpation and successful wars of Grimoald—Reigns of Berthari and Cunibert—Quarrels of the Papacy and the empire—The exile of Pope Martin I.—Gradual alienation of Italy from the empire—Civil wars of Aribert II. and Ansprand—Successful reign of Liutprand—Leo the Isaurian and Gregory II.—Italy rebels against the Iconoclasts—Liutprand conquers most of the Exarchate. After the death of Rothari the law-giver the Lombard kingdom entered into its second stage: it had now almost reached the full growth of its territorial extension, and had settled down into its final shape. For nearly a hundred years the main events of its political history are civil wars, or defensive campaigns against its two neighbours, the Roman exarch and the Chagan of the Avars. There is no sustained effort either to expel the Imperialists from Italy, or to extend the boundary of the Lombard realm to the north. It was only in the middle of the eighth century that the estrangement between Constantinople and its Roman subjects in Italy led to such a weakening of the Imperial authority, that the Lombard kings were able to seize the long-coveted Exarchate. The history of the cutting short of the dominions of the eastern Caesar beyond the Adriatic turns much more on the growth of the Papal power, and on the quarrel on the subject of Iconoclasm, which sundered the churches of Rome and Constantinople, than on the ambition or ability of the rulers of Lombardy. On the murder of Rothari’s short-lived son in 653, the Lombards elected as their king Aribert, a nephew of the sainted queen Theodelinda, whose name was still held in kindly memory all over the land. [Sidenote: Aribert I. 653-62.] Count Gundoald, Aribert’s father, had long been settled in Italy: he had crossed the Alps with his pious sister more than half a century before, so that Aribert himself was counted a Lombard, and not a Bavarian. The new king reigned obscurely for nine years (653-62): he waged no wars and was mainly noted as a friend of the clergy and a builder of churches. He was a fervent Catholic, and did his best to root out the few traces of Arianism yet remaining in Lombardy. The land had peace under his sway, but ere he died he sowed the seeds of future troubles by the unhappy inspiration which led him to induce the Lombard Witan to elect his two sons, Godebert and Berthari, as joint heirs to the kingship.