about his land frontier but also used up strength
which might have made head against the Tartars. Constantinople then, as
now, was detached from the Balkans. The Osmanlis, had they possessed
themselves of it, might well have let the latter be for a long time to
come. Instead, they had to battle, with the help now of one section of the
Balkan peoples, now of another, till forced to make an end of all their
feuds and treacheries by annexations after the victories of Kosovo in 1389
and Nikopolis in 1396.

Nor was this all. They became involved also with certain peoples of the
main continent of Europe, whose interests or sympathies had been affected
by those long and sanguinary Balkan wars. There was already bad blood and
to spare between the Osmanlis on the one hand, and Hungarians, Poles, and
Italian Venetians on the other, long before any second opportunity to
attack Constantinople occurred: and the Osmanlis were in for that age-long
struggle to secure a 'scientific frontier' beyond the Danube, whence the
Adriatic on the one flank and the Euxine on the other could be commanded,
which was to make Ottoman history down to the eighteenth century and spell
ruin in the end.

It is a vulgar error to suppose that the Osmanlis set out for Europe, in
the spirit of Arab apostles, to force their creed and dominion on all the
world. Both in Asia and Europe, from first to last, their expeditions and
conquests have been inspired palpably by motives similar to those active
among the Christian powers, namely, desire for political security and the
command of commercial areas. Such wars as the Ottoman sultans, once they
were established at Constantinople, did wage again and again with knightly
orders or with Italian republics would have been undertaken, and fought
with the same persistence, by any Greek emperor who felt himself strong
enough. Even the Asiatic campaigns, which Selim I and some of his
successors, down to the end of the seventeenth century, would undertake,
were planned and carried out from similar motives. Their object was to
secure the eastern basin of the Mediterranean by the establishment of some
strong frontier against Iran, out of which had come more than once forces
threatening the destruction of Ottoman power. It does not, of course, in
any respect disprove their purpose that, in the event, this object was
never attained, and that an unsatisfactory Turco-Persian border still
illustrates at this day the failures of Se