were now regarded by Rome as schismatical. Chief among these were the
date of celebrating Easter, and the uncanonical method of cutting the
tonsure in a crescent instead of a circle. Augustine, shortly after his
arrival, endeavoured to obtain unity between the two churches on these
matters of discipline, to which great importance was attached as tests
of submission to the Latin rule. He obtained from Æthelberht a
safe-conduct through the heathen West-Saxon territories as far as what
is now Worcestershire; and there, "on the borders of the Huiccii and
the West-Saxons," says Bæda, "he convened to a colloquy the bishops and
doctors of the nearest province of the Britons, in the place which, to
the present day, is called in the English language, Augustine's Oak."
Such open-air meetings by sacred trees or stones were universal in
England both before and after its conversion. "He began to admonish them
with a brotherly admonition to embrace with him the Catholic faith, and
to undertake the common task of evangelising the pagans. For they did
not observe Easter at the proper period: moreover, they did many other
things contrary to the unity of the Church." But the Welsh were jealous
of the intruders, and refused to abandon their old customs. Thereupon,
Augustine declared that if they would not help him against the heathen,
they would perish by the heathen. A few years later, after Augustine's
death, this prediction was verified by Æthelfrith of Northumbria, whose
massacre of the monks of Bangor has already been noticed.

It was in return for the destruction of Chester and the slaughter of the
monks that Cadwalla joined the heathen Penda against his fellow
Christian Eadwine. But the death of Eadwine left the throne open for the
house of Æthelfrith, whose place Eadwine had taken. After a year of
renewed heathendom, however, during part of which the Welsh Cadwalla
reigned over Northumbria, Oswald, son of Æthelfrith, again united Deira
and Bernicia under his own rule. Oswald was a Christian, but he had