Almost simultaneously with his accession, Louis committed an act more serious and compromising. He had, by his wife Hermengarde, three sons, Lothaire, Pepin, and Louis, aged respectively nineteen, eleven, and eight. In 817 Louis summoned at Aix-la-Chapelle the general assembly of his dominions; and there, whilst declaring that “neither to those who were wisely-minded, nor to himself, did it appear expedient to break up, for the love he bare his sons and by the will of man, the unity of the empire, preserved by God himself,” he had resolved to share with his eldest son, Lothaire, the imperial throne. Lothaire was in fact crowned emperor; and his two brothers, Pepin and Louis, were crowned king, “in order that they might reign, after their father’s death and under their brother and lord, Lothaire, to wit: Pepin, over Aquitaine and a great part of Southern Gaul and of Burgundy; Louis, beyond the Rhine, over Bavaria and the divers peoplets in the east of Germany.” The rest of Gaul and of Germany, as well as the kingdom of Italy, was to belong to Lothaire, emperor and head of the Frankish monarchy, to whom his brothers would have to repair year by year to come to an understanding with him and receive his instructions. The last-named kingdom, the most considerable of the three, remained under the direct government of Louis the Debonnair, and at the same time of his son Lothaire, sharing the title of emperor. The two other sons, Pepin and Louis, entered, notwithstanding their childhood, upon immediate possession, the one of Aquitaine and the other of Bavaria, under the superior authority of their father and their brother, the joint emperors. Charlemagne had vigorously maintained the unity of the empire, for all that he had delegated to two of his sons, Pepin and Louis, the government of Italy and Aquitaine, with the title of king. Louis the Debonnair, whilst regulating beforehand the division of his dominion, likewise desired, as he said, to maintain the unity of the empire. But he forgot that he was no Charlemagne. It was not long before numerous mournful experiences showed to what extent the unity of the empire required personal superiority in the emperor, and how rapid would be the decay of the fabric when there remained nothing but the title of the founder.