s was
postponed to the following _Riksdag_ (see SWEDEN: _History_). On the
10th of July Charles quitted Sweden to engage in his Polish adventure.
By the time war was declared he had at his disposal 50,000 men and 50
warships. Hostilities had already begun with the occupation of Dunaburg
(Dvinsk) in Polish Livonia by the Swedes (July 1, 1655), and the Polish
army encamped among the marshes of the Netze concluded a convention
(July 25) whereby the palatinates of Posen and Kalisz placed themselves
under the protection of the Swedish king. Thereupon the Swedes entered
Warsaw without opposition and occupied the whole of Great Poland. The
Polish king, John Casimir, fled to Silesia. Meanwhile Charles pressed on
towards Cracow, which was captured after a two months' siege. The fall
of Cracow extinguished the last hope of the boldest Pole; but before the
end of the year an extraordinary reaction began in Poland itself. On the
18th of October the Swedes invested the fortress-monastery of
Czenstochowa, but the place was heroically defended; and after a seventy
days' siege the besiegers were compelled to retire with great loss.

This astounding success elicited an outburst of popular enthusiasm which
gave the war a national and religious character. The tactlessness of
Charles, the rapacity of his generals, the barbarity of his mercenaries,
his refusal to legalize his position by summoning the Polish diet, his
negotiations for the partition of the very state he affected to
befriend, awoke the long slumbering public spirit of the country. In the
beginning of 1656 John Casimir returned from exile and the Polish army
was reorganized and increased. By this time Charles had discovered that
it was easier to defeat the Poles than to conquer Poland. His chief
object, the conquest of Prussia, was still unaccomplished, and a new foe
arose in the elector of Brandenburg, alarmed by the ambition of the
Swedish king. Charles forced the elector, indeed, at the point of the
sword to become his ally and vassal (treaty of Konigsberg, Jan. 17,
1656); but the Polish national rising now imperatively demanded his
presence in the south. For weeks he scoured the interminable
snow-covered plains of Poland in pursuit of the Polish guerillas,
penetrating as far south as Jaroslau in Galicia, by which time he had
lost two-thirds of his 15,000 men with no apparent result. His retreat
from Jaroslau to Warsaw, with the fragments of his host, amidst three
convergin