th Ouzoun Hassan, chief of the
Turkomans of the White Horde, whose daring courage and rapid career of
conquest made him, in the general estimation, a formidable rival of
Mohammed II.

When invited to join in the league against Mohammed, Hassan demanded as
the price of his assistance the hand of the emperor's daughter
Katherine, renowned throughout the Orient as the most beautiful virgin
in the East. John IV. was highly pleased at the prospect of purchasing
so powerful an alliance on such easy terms, and readily agreed,
doubtless without consulting the fair Katherine. Yet, in order to save
his credit as a Christian emperor, and perhaps as a balm to his own
conscience in sacrificing his daughter to an infidel, he stipulated in
the treaty that Katherine should be permitted always the exercise of her
own religion, and should have the privilege of keeping a certain number
of Christian ladies as her attendants, and of Greek priests in her
suite, to serve a private chapel in the harem. It is to the honor of a
Mussulman to observe that Hassan strictly kept his promises, even after
the empire of Trebizond and the house of Grand-Comnenus were no more.

Before this matrimonial alliance was fulfilled, John came to his end;
but his brother David, who displaced the heir and usurped the throne,--a
fit agent for consummating the ruin of an empire,--completed the
arrangement. The beautiful Katherine was sent with suitable pomp to the
court of her bridegroom, Hassan, and readily adapted herself to the
changed conditions of her life. She soon acquired great influence over
her infidel husband, who was the soul of honor and good faith, and in
every phase of her life which is known to us she showed herself the most
attractive character of the whole house of Comnenus.

But no matrimonial alliance could save the doomed empire. Constantinople
had fallen in 1453, and it was merely a matter of time when the last
surviving Greek kingdom should succumb to the Mohammedan yoke. Mohammed
II., by the exercise of intrigue, gradually detached from the emperor
his infidel allies. When finally the Mohammedan forces came against the
city, David showed that he possessed nothing of the heroic spirit of the
last Constantine. He offered but a feeble resistance, and readily
sacrificed the city to outrage and plunder on an assurance of safety for
himself and his family. David basely deserted his empire and embarked on
board one of the Turkish galleys, with his