was due entirely to his steadfast adherence to these
principles that Poland in the course of the 15th century rose to the
rank of a great power; but by a singular irony of fate, Casimir, in
consequence of his unswerving efforts to make his country glorious and
prosperous, entirely forfeited the popularity of his Polish subjects,
whose true interests he understood far better than they did themselves.
Thus his refusal to sacrifice Polish to Lithuanian or Lithuanian to
Polish interests caused both Poles and Lithuanians to accuse the
far-seeing monarch of partiality and favouritism; while his anti-German
policy, on which the future safety of the dual state depended, could
only be carried through by the most humiliating concessions to patrician
pride and greed. His difficulties were moreover considerably enhanced by
the fact that he was not of an essentially martial temperament, and
could not therefore appeal to the heroic side of the Polish character.

The great triumph of Casimir's reign was the final subjugation of the
Teutonic Order, a triumph only accomplished after a harassing and
desultory thirteen years' war, during which Casimir's own subjects gave
him more trouble than all his enemies. The pretext of the rupture was
the attempt of the knights to crush the Prussian diet, which, bearing
as it did most of the burdens, claimed fairly enough a proportionate
share in the government of the Prussian provinces. Excommunicated by the
pope and placed under the ban of the Empire, the Prussian cities and
gentry naturally turned to their nearest neighbour, Poland, for
protection. In October 1453 they placed themselves beneath the
overlordship of Casimir; on the 4th of February 1454 formally renounced
their ancient allegiance to the Order; and some weeks later captured no
fewer than fifty-seven towns and castles. On the 6th of March 1454
Casimir issued a manifesto directing the incorporation of the Prussian
provinces with Poland, but granting them at the same time freedom from
taxation and full autonomy. But except in the border province of Great
Poland, the acquisition of this new territory excited little interest
and no enthusiasm in Poland generally. The local diets granted subsidies
with a niggard hand, and for the conduct of the war the king soon had to
depend almost entirely on Hussite mercenaries, who frequently turned
against him when their wages were not paid. The Polish gentry on the
other hand exhibited far less energy