The years 1648 to 1667 are conventionally referred to in Polish historiography as the Potop — the Deluge — after Henryk Sienkiewicz's 1886 historical novel of that title. They are the most catastrophic single period in the country's history before the partitions, and probably the most catastrophic single period in the history of any European state of comparable size in the seventeenth century. In nineteen years the Commonwealth's population fell by something like thirty-five percent — from approximately eleven million to approximately seven million. Cities were sacked: Warsaw three times, Vilnius once (to the ground, in 1655, the worst single event in that city's history before 1941). The Commonwealth's eastern frontier was pushed back; the Ukrainian lands were lost to Moscow; the Baltic provinces were lost to Sweden. None of these losses was permanent in the same year, but the structural weakening of the Commonwealth that they caused was. The country that emerged in 1667 from the wars was a different and substantially weaker country than the one that had entered them in 1648.
How it began — the Khmelnytsky uprising
The Deluge began in May 1648 with a Cossack uprising on the Commonwealth's southern frontier. The Zaporozhian Cossacks were a quasi-autonomous military society of Orthodox Ruthenians inhabiting the Dnieper frontier with the Tatar khanate of Crimea; they had been at intermittent odds with the Commonwealth for fifty years over issues of religious freedom, the registration of Cossack regiments as state troops, and the relationship between the Cossack military caste and the Polish szlachta who controlled the agricultural estates in the Ukrainian lands. In 1648 a Cossack officer named Bohdan Khmelnytsky, with personal grievances against a local Polish magnate and Tatar military backing, raised a Cossack-Tatar army and crushed the Commonwealth's eastern field force in two engagements at Zhovti Vody and Korsuń (May 1648). The Polish hetmans were captured.
What followed was a five-year war that destroyed the social order of Ukraine. Cossack and Tatar forces advanced as far as Lviv and Zamość. Peasant uprisings against the Polish szlachta and the Polish-Jewish leaseholders (the arendars) killed perhaps a hundred thousand civilians in the first year alone. The Jewish population of Ukraine was particularly badly hit: substantial communities at Tulchyn, Nemyriv, Ostropol and Polonne were massacred during the campaign. The Polish field forces, reorganised under King John II Casimir, fought a series of indecisive engagements (Zborów 1649, Beresteczko 1651, Bila Tserkva 1651) without subduing the Cossack lands. In January 1654 Khmelnytsky concluded the Pereyaslav Agreement with Moscow, transferring the Cossack Hetmanate from Polish to Russian suzerainty in exchange for Russian military intervention. The Russian army crossed the Dnieper that summer.
The Swedish invasion
In July 1655, with the Commonwealth's army committed to the eastern war, the king of Sweden, Charles X Gustav, declared war on Poland-Lithuania, citing a long list of dynastic grievances and a more immediate strategic interest in preventing Russia from dominating the Baltic. The Swedish army crossed into Greater Poland from Pomerania. The Polish forces opposing them surrendered at Ujście on the 25th of July, almost without resistance — the magnate Krzysztof Opaliński, who led the surrender, would be remembered for it in unflattering terms by every Polish historian since. Warsaw fell to the Swedes in early September. Kraków fell on the 17th of October. By December the king, John II Casimir, had fled the country and was in exile at Głogówek in Silesia. Most of the Commonwealth's senators had accepted Charles X as their sovereign.
What turned the war was not military force but two pieces of religious symbolism. The first was the unsuccessful Swedish siege of the Jasna Góra monastery at Częstochowa, which contained the country's most venerated Marian image, the Black Madonna. The monastery — defended by about 250 monks, militia and noble volunteers under the prior Augustyn Kordecki — held out for forty days (18 November to 27 December 1655) against a Swedish force of about 3,000. The siege was lifted on the 27th of December when the Swedes withdrew rather than commit reinforcements. The defence became, almost immediately, a national symbol: a clear instance of Catholic victory against a Protestant aggressor at a time when most of the Commonwealth's secular elite had accepted Protestant rule. The second was the king's vow at Lwów in April 1656 — the Lwowskie Śluby — in which the returning John II Casimir formally consecrated the Commonwealth to the protection of the Virgin Mary and declared her Queen of Poland, a constitutional formula that has survived in Polish Catholic liturgy to this day.
Behind the symbolism, a Polish guerrilla revival was under way. The hetman Stefan Czarniecki led increasingly successful operations against the Swedish supply lines and isolated garrisons through 1656 and 1657. The Commonwealth's eastern army, after defeating a Transylvanian army under George II Rákóczi who had joined the Swedish side in 1657, was redirected westward. By 1657 the Habsburgs had been brought in as Polish allies; by 1658 the Brandenburger elector Frederick William had switched sides (his price was the recognition of his sovereign rule over East Prussia, the formal birth of the Hohenzollern Kingdom of Prussia in slow motion). By 1660 the Swedes had been pushed out. The Treaty of Oliva of May 1660 ended the war.
The Andrusovo settlement
The war with Russia lasted longer — into 1667 — and the settlement was less favourable. The Treaty of Andrusovo of January 1667 partitioned the Cossack Hetmanate along the Dnieper river: the right-bank Ukraine (west of the Dnieper) remained Polish-Lithuanian; the left-bank Ukraine (east of the Dnieper) plus Kiev itself (initially on a two-year lease, in fact permanently) became Russian. Smolensk, lost to the Commonwealth in 1611 and recovered intermittently since, was permanently transferred to Russia. The Commonwealth's eastern frontier, which in 1648 had run to the Dnieper Rapids and the Crimean steppe, now retreated by roughly 200 kilometres on a 700-kilometre front.
The cost
The demographic and economic cost of the Deluge was staggering. The 1657 population of the Commonwealth was about seven million, against perhaps eleven million in 1648; the four-million deficit is the standard pre-modern Polish historians' estimate (more recent studies suggest the loss may have been somewhat smaller but still on the order of three million). Cities were ruined: Warsaw lost something like ninety percent of its built fabric; Vilnius was burned almost entirely; Lublin and Kraków were sacked. The Jewish communities of Ukraine, Volhynia and parts of Lithuania were destroyed; modern Holocaust historians regard the Deluge as one of the demographic disasters from which the Polish Jewish population took a century and a half to recover. The economic infrastructure of the country — the Vistula grain trade, the dyepit trade in Royal Prussia, the Lithuanian-Inflanty Baltic trade — was disrupted for a generation.
The structural consequence, however, was more lasting than the immediate damage. The Deluge demonstrated that the Commonwealth could not defend its frontiers against simultaneous attacks. Its army was too small; its tax base was too weak; its central government was too constrained by the Sejm and the liberum veto to mobilise rapidly. The next century and a half of Polish history would, in substantial part, be the story of Polish reformers attempting to address these structural weaknesses while their three increasingly powerful neighbours worked, with progressive efficiency, to prevent them from doing so. The recovery of the late seventeenth century — under John III Sobieski, the subject of the next chapter — was a real one. It was also the last full recovery the Commonwealth would ever experience.
End of Chapter V