[55] The Act imposed Christianity in Lithuania and transformed Poland into a diarchy, a kingdom ruled over by two sovereigns; their descendants and successive monarchs held the titles of king and grand duke respectively.

[78] However, his successful Livonian campaign ended in the annexation of Livonia and the Duchy of Courland and Semigallia (modern-day Estonia and Latvia, respectively), thus expanding the Commonwealth's influence into the Baltics.

[90] The Polish–Ottoman War (1620–21) forced Poland to withdraw from Moldavia in southeastern Europe, but Sigismund's victory over the Turks at Khotyn diminished the supremacy of the Sultanate and eventually led to the murder of Osman II.

[93] During this period, Poland was experiencing a cultural awakening and extensive developments in arts and architecture; the first Vasa king openly sponsored foreign painters, craftsmen, musicians and engineers, who settled in the Commonwealth at his request.

[citation needed] A major rebellion of self-governed Ukrainian Cossacks inhabiting south-eastern borderlands of the Commonwealth rioted against Polish and Catholic oppression of Orthodox Ukraine in 1648, in what came to be known as the Khmelnytsky Uprising.

[citation needed] In the late 17th century, the king of the weakened Commonwealth, John III Sobieski, allied with Holy Roman Emperor Leopold I to deal crushing defeats to the Ottoman Empire.

In spite of his controversial means of attaining power, Augustus II lavishly spent on the arts and left an extensive cultural and architectural (Baroque) legacy in both countries.

The Sejm could veto the king on important matters, including legislation (the adoption of new laws), foreign affairs, declaration of war, and taxation (changes of existing taxes or the levying of new ones).

[citation needed] Furthermore, aside from notable exceptions such as the able Stefan Batory from Transylvania (1576–86), the kings of foreign origin were inclined to subordinate the interests of the Commonwealth to those of their own country and ruling house.

[146] The economy of the Commonwealth was predominantly based on agricultural output and trade, though there was an abundance of artisan workshops and manufactories – notably paper mills, leather tanneries, ironworks, glassworks and brickyards.

[151] The country played a significant role in the supply of Western Europe by the export of grain (rye), cattle (oxen), furs, timber, linen, cannabis, ash, tar, carminic acid and amber.

[156][157] The land routes, mostly to the German provinces of the Holy Roman Empire such as the cities of Leipzig and Nuremberg, were used for the export of live cattle (herds of around 50,000 head) hides, salt, tobacco, hemp and cotton from the Greater Poland region.

[181] Several years before the Union of Lublin, the Polish obrona potoczna was reformed, as the Sejm (national parliament of Poland) legislated in 1562–1563 the creation of wojsko kwarciane, named after kwarta tax levied on the royal lands for the purpose of maintaining this formation.

It was famous for its rare quasi-democratic political system, praised by philosophers, and during the Counter-Reformation was known for near-unparalleled religious tolerance, with peacefully coexisting Roman Catholic, Jewish, Orthodox Christian, Protestant and Muslim (Sufi) communities.

[187] Commonwealth scientists included: Martin Kromer (1512–1589), historian and cartographer; Michael Sendivogius (1566–1636), alchemist and chemist; Jan Brożek (Ioannes Broscius in Latin) (1585–1652), polymath: a mathematician, physician and astronomer; Krzysztof Arciszewski (Crestofle d'Artischau Arciszewski in Portuguese) (1592–1656), engineer, ethnographer, general and admiral of the Dutch West Indies Company army in the war with the Spanish Empire for control of Brazil;[188] Kazimierz Siemienowicz (1600–1651), military engineer, artillery specialist and a founder of rocketry; Johannes Hevelius (1611–1687), astronomer, founder of lunar topography; Michał Boym (1612–1659), orientalist, cartographer, naturalist and diplomat in Ming Dynasty's service (Pic.

[193] Polish monarchs and nobles frequently invited and sponsored foreign painters and artisans, notably from the Low Countries (the Netherlands, Flanders and Belgium), Germany or Italy.

[199] The religious cultures of Poland–Lithuania coexisted and penetrated each other for the entirety of the Commonwealth's history – the Jews adopted elements of the national dress,[200] loanwords and calques became commonplace and Roman Catholic churches in regions with significant Protestant populations were much simpler in décor than those in other parts of Poland–Lithuania.

Sigismund III brought in Italian composers and conductors, such as Luca Marenzio, Annibale Stabile, Asprilio Pacelli, Marco Scacchi and Diomedes Cato for the royal orchestra.

Notable home grown musicians, who also composed and played for the King's court, included Bartłomiej Pękiel, Jacek Różycki, Adam Jarzębski, Marcin Mielczewski, Stanisław Sylwester Szarzyński, Damian Stachowicz, Mikołaj Zieleński and Grzegorz Gorczycki.

Neoclassicism replaced Baroque by the second half of the 18th century – the last ruler of the Poland–Lithuania, Stanisław August Poniatowski, greatly admired the classical architecture of Ancient Rome and promoted it as a symbol of the Polish Enlightenment.

Sarmatism enshrined equality among szlachta, horseback riding, tradition, provincial quaint life in manor houses, peace and pacifism; championed oriental-inspired souvenirs or attire for men (żupan, kontusz, sukmana, pas kontuszowy, delia, szabla); favoured European Baroque architecture; endorsed Latin as a language of thought or expression; and served to integrate the multi-ethnic nobility by creating an almost nationalistic sense of unity and of pride in Golden Liberty.

[145] In its early, idealistic form, Sarmatism represented a positive cultural movement: it supported religious belief, honesty, national pride, courage, equality and freedom.

[218] There were also considerable numbers of Czechs, Hungarians, Livonians, Romanis, Vlachs, Armenians, Italians, Scots, and the Dutch (Olędrzy), who were either categorised as merchants, settlers or refugees fleeing religious persecution.

[221] Historians Michał Kopczyński and Wojciech Tygielski suggest that with the territorial expansion after the Truce of Deulino in 1618, the Commonwealth's population reached 12 million people, of which Poles constituted only 40%.

The Warsaw Confederation signed on 28 January 1573 secured the rights of minorities and religions;[20] it allowed all persons to practice any faith freely, though religious tolerance varied at times.

As outlined by Norman Davies, "the wording and substance of the declaration of the Confederation of Warsaw of were extraordinary with regards to prevailing conditions elsewhere in Europe; and they governed the principles of religious life in the Republic for over two hundred years.

[232]To be Polish, in remote and multi-ethnic parts of the Commonwealth, was then much less an index of ethnicity than of religion and rank; it was a designation largely reserved for the landed noble class (szlachta), which included Poles, but also many members of non-Polish origin who converted to Catholicism in increasing numbers with each following generation.

Moreover, the decades of peace brought huge colonization efforts to the eastern territories (nowadays roughly western and central Ukraine),[237] heightening the tensions among nobles, Jews, Cossacks (traditionally Orthodox), Polish and Ruthenian peasants.

The tensions were aggravated by conflicts between Eastern Orthodoxy and the Greek Catholic Church following the Union of Brest, overall discrimination of Orthodox religions by dominant Catholicism,[238] and several Cossack uprisings.

[citation needed] The lands that once belonged to the Commonwealth are now largely distributed among several Central and East European countries: Poland, Ukraine, Moldova (Transnistria), Belarus, Russia, Lithuania, Latvia, and Estonia.