The forgotten third English province

I was reading through Bishop Moorman's A History of the Church in England the other day and ran across this little historical detail which I had forgotten--the short-lived third ecclesiastical province of the church of England, the province of Lichfield. Here is the excerpt from his book:

In the second half of the eighth century it was the turn of Mercia to reach such a position [of prominence over the other kingdoms on the island]. Under the wise and powerful rule of King Offa (757-96), Mercia rose to such power that its king claimed to be 'king of all the English' though such a claim would, no doubt, have been challenged in many parts of the country. Offa was undoubtedly much the greatest ruler of his generation in England. A man of big ideas, he was one of the few English rulers who had a definite foreign connection, corresponding both with the pope and with Charlemagne. He was also a great benefactor to the Church and the founder of many monasteries.

Yet his policy with regard to the Church was mistaken. At a time when the Church was the only real unifying force in the country, Offa conceived a plan for separating Mercia from the rest of the pro­vince of Canterbury and giving it its own archbishop. Such a desire sprang from patriotism and zeal for his own kingdom; but it was disastrous for the Church. It meant that, at the moment when the Church of the southern province was beginning to act strongly and unitedly in the cause of reform, it was to be split into two. Offa, how­ever, was determined to carry out his project and invited the pope to send to England two legates with power to carry through such a division of the province.

The two legates, George, Cardinal-Bishop of Ostia, and Theophylact, Cardinal-Bishop of Todi, arrived in England in 786, the first of a long series of papal legates who were later to play an important part in the history of England. They made a visitation not only of the southern but also of the northern province and held councils at 'Pincahala' (probably Finchale near Durham) and at Celchyth or Chelsea, both in 787. At both these councils decrees were passed, similar to those promulgated by other reforming councils, and in the same year they succeeded in carrying out the primary purpose of their visit which was to give authority for the division of the southern province into two. Offa thus achieved his ambition; Lichfield became a metropolitan see with its own archbishop and six other dioceses under its jurisdiction—Worcester, Hereford, Leicester, Sherbome, Elmham and Dunwich—leaving only Rochester, London, Winchester and Selsey to the Archbishop of Canterbury. This arrangement lasted until a few years after the death of Offa, but was brought to an end in 803.