th their sister only a month after the death of his own queen
in September; and a joint attack was planned upon Henry. His answer was
rapid and decisive. Margaret was in his keeping, and he at once married
her to his son, took the Vexin into his own hands and fortified it with
castles. His position in fact was so strong that the forced his enemies
to a truce in June 1161.

The political complications with which Henry was surrounded were still
further confused by a new question which now arose, and which was to
threaten the peace of Europe for eighteen years. On the death of the
English Pope, Hadrian IV., on the 1st of September 1159, two rivals,
Alexander III. and Victor IV., disputed the see of Rome, and the strife
between the Empire and the Papacy, now nearly one hundred years old,
broke out afresh on a far greater scale than in the time of Gregory.
Frederick Barbarossa asserted the imperial right of judging between the
rivals, and declared Victor pope, supported by the princes of the Empire
and by the kings of Hungary, Bohemia, and Denmark. Alexander claimed the
aid of the French king--the traditional defender of the Church and
protector of the Popes; and after the strife had raged for nearly three
years, he fled in 1162 to France. In the great schism Henry joined the
side of Louis in support of Alexander and of the orthodox cause; the two
kings met at Chouzy, near Blois, to do honour to the Pope; they walked
on either side of his horse and held his reins. The meeting marked a
great triumph for Alexander; the union of the Teutonic nations against
the policy of Rome was to be delayed for three centuries and a half. It
marked, too, the highest point of Henry's success. He had checked the
Emperor's schemes; he had won the gratitude of both Louis and the Pope;
he had defeated the plots of the House of Blois, and shown how easily
any alliance between France and Champagne might be broken to pieces by
his military power and his astute diplomacy. He had rounded off his
dominions; he had conquered the county of Cahors; he had recovered the
Vexin and the border castles of Freteval and Amboise; the fiefs of
William of Boulogne had passed into his hands on William's death; he was
master of Nantes and Dol, and lord of Britanny; he had been appointed
Protector of Flanders.

At this moment, indeed, Henry stood only second to the Emperor among the
princes of Christendom, and his aim seems to have been to rival in
some sort the Empi