Alcuin’s system included, besides the palace school, and the monastic and cathedral schools, which in some instances gave both elementary and superior instruction, all the parish or village elementary schools, whose head was the parish priest.
In 790, seeing his plans well established, Alcuin returned to York bearing letters of reconciliation to Offa, King of Mercia, between whom and Charlemagne dissension had arisen. Having accomplished his errand, he went back to the German court in 792. Here his first act was to take a vigorous part in the furious controversy respecting the doctrine of Adoptionism. Alcuin not only wrote against the heresy, but brought about its condemnation by the Council of Frankfort, in 794.
Two years later, at his own request, he was made Abbot of the Benedictine monastery of St. Martin, at Tours. Not contented with reforming the lax monastic life, he resolved to make Tours a seat of learning. Under his management, it presently became the most renowned school in the kingdom. Especially in the copying of manuscripts did the brethren excel. Alcuin kept up a vast correspondence with Britain as well as with different parts of the Frankish kingdom; and of the two hundred and thirty letters preserved, the greater part belonged to this time. In 799, at Aachen, he held a public disputation on Adoptionism with Felix, Bishop of Urgel, who was wholly vanquished. When the king, in 800, was preparing for that visit to the Papal court which was to end with his coronation as Emperor of the Holy Roman Empire, he invited Alcuin to accompany him. But the old man, wearied with many burdens, could not make the journey. By the beginning of 804 he had become much enfeebled. It was his desire, often expressed, to die on the day of Pentecost. His wish was fulfilled, for he died at dawn on the 19th of May. He was buried in the Cloister Church of St. Martin, near the monastery.