(Cambridge Concise Histories) Jerzy Lukowski, Hubert Zawadzki - A Concise History of Poland-Cambridge University Press (2006)

And yet the Rzeczpospolita showed itself capable of bursts of astonishing energy and resilience in the face of invasion and rebellion. The Union of Lublin of 1569 went a long way to opening up the Lithuanian lands to the Crown szlachta, restrictions in the 1588 Lithuanian Statute notwithstanding. And, of course, there was now no impediment to seeking new w'ealth in the Rus’ lands incorporated into the Crown. The wars against Muscovy were no longer a Lithuanian preserve - they became of vital interest to the Commonwealth in its entirety. The campaigns of Stefan Batory between Г578 and 1582 reversed the territorial gains notched up by Ivan IV, securing Livonia and Polotsk. Batory owed much of his success to his close collaboration with Jan Zamoyski, grand chancellor and grand hetman (commander-in-chief) of the Crown, the richest magnate of all Poland, a highly cultured demagogue turned statesman, the closest that Poland produced to a royal ‘favourite’ in the mould of a Buckingham, a Richelieu or an Olivares. He had been one of the leading lights of the Executionist movement, and an increasingly close collaborator of Sigismund II. It was Zamoyski who had mobilized the nobility during the first interregnum to go for vintim royal election, not least because he felt this was the surest means of excluding the Habsburgs. He assured the szlachta that they were the foundation of a Commonwealth superior even to Republican Rome. He went down well. Instrumental in bringing about Batory’s election, he was rewarded with almost limitless royal patronage and the highest offices in the land. His massive clientele was invaluable in maintaining support for the new king, in whose service he demonstrated military as well as political and administrative talent. Between them the two men oversaw the emergence of a veteran military cadre which was to render sterling service over the next generation.

Sigismund Ill’s reign witnessed even more remarkable successes. Intervention in Russia during the later reign of Boris Godunov and the ‘Time of Troubles’ saw a Polish-backed pretender briefly placed on the Muscovite throne in May 1606. In 1610, Russian boyars elected Sigismund’s 15-year-old son, Wladyslaw, as tsar. Though the prince never entered Moscow, the city received a Polish garrison in September 1610, which, in the face of a massive uprising, held out in the Kremlin until October 1611. The election of Michael Romanov in March 1613 gave the Russians a ruler around whom to unite, but it was years before Polish troops and Cossack freebooters were cleared from Russian soil. In 1618, Russia ceded Smolensk to the Commonwealth. Michael Romanov’s attempt to recapture it during the ‘Smolensk war’ of 1632-4 ended in humiliation. The ‘Perpetual’ peace of Polanovo of June 1634 left Smolensk in Polish hands. Nothing seemed more emphatically to proclaim the strength of the new state created by the Union of Lublin.

Some of these achievements pointed to shortcomings, as well as strengths, in the Polish-Lithuanian polity. The Russian adventure of 1606 was begun as a private initiative by irresponsible grandees seeking to exploit the disorders of Boris Godunov’s reign. By the time the Sejm approved involvement in 1609, the opportunities seemed too good to ignore. Likewise, the semi-private initiatives of ambitious border magnates at the turn of the sixteenth and seventeenth centuries aimed to reassert Poland’s dormant influence over Moldavia and Wallachia. This courted disaster, for such undertakings could only jeopardize the good relations established with the Porte by the Jagiellonians. Unofficial, destructive raids by Poland’s Cossacks against Turkish possessions on the Black Sea aggravated matters. The 1620 expedition under Crown grand hetman Stanislaw Zolkiewski, to keep a friendly hospodar on the Moldavian throne, suffered a crushing defeat at Turkish hands at Tutora. Poland was fortunate that domestic troubles in Turkey weakened its ability to launch a full-scale counter-offensive and facilitated the defeat of the Turkish punitive expedition of 1621 at Khotin, just inside Moldavia.