llow it form the grandest portion of his
reign. While Rome was threatening excommunication he added a new realm to
his dominions. Ireland had long since fallen from the civilization and
learning which its missionaries brought in the seventh century to the
shores of Northumbria. Every element of improvement or progress which had
been introduced into the island disappeared in the long and desperate
struggle with the Danes. The coast-towns which the invaders founded, such
as Dublin or Waterford, remained Danish, in blood and manners and at feud
with the Celtic tribes around them, though sometimes forced by the
fortunes of war to pay tribute and to accept the overlordship of the
Irish kings. It was through these towns however that the intercourse with
England which had ceased since the eighth century was to some extent
renewed in the eleventh. Cut off from the Church of the island by
national antipathy, the Danish coast-cities applied to the See of
Canterbury for the ordination of their bishops, and acknowledged a right
of spiritual supervision in Lanfranc and Anselm. The relations thus
formed were drawn closer by a slave-trade between the two countries which
the Conqueror and Bishop Wulfstan succeeded for a time in suppressing at
Bristol but which appears to have quickly revived. In the twelfth century
Ireland was full of Englishmen who had been kidnapped and sold into
slavery in spite of royal prohibitions and the spiritual menaces of the
English Church. The slave-trade afforded a legitimate pretext for war,
had a pretext been needed by the ambition of Henry the Second; and within
a few months of that king's coronation John of Salisbury was despatched
to obtain the Papal sanction for an invasion of the island. The
enterprise, as it was laid before Pope Hadrian IV., took the colour of a
crusade. The isolation of Ireland from the general body of Christendom,
the absence of learning and civilization, the scandalous vices of its
people, were alleged as the grounds of Henry's action. It was the general
belief of the time that all islands fell under the jurisdiction of the
Papal See, and it was as a possession of the Roman Church that Henry
sought Hadrian's permission to enter Ireland. His aim was "to enlarge the
bounds of the Church, to restrain the progress of vices, to correct the
manners of its people and to plant virtue among them, and to increase the
Christian religion." He engaged to "subject the people to laws, to
extirpa