Poland, in Toruń, on the initiative of King Władysław IV Vasa, a three-month congress of European Catholics, Lutherans and Calvinists was held, known as Colloquium Charitativum; an important event in the history of interreligious dialogue. During the Great Northern War (1700–21), the city was besieged by Swedish troops. The restoration of Augustus II the Strong as King of Poland was prepared in the city in the Treaty of Thorn (1709) by Russian Tsar Peter the Great. In the second half of the 17th century, tensions between Catholics and Protestants grew, similarly to religious wars throughout Europe. In the early 18th century about 50 percent of the populace, especially the gentry and middle class, were German-speaking Protestants, while the other 50 percent were Polish-speaking Roman Catholics. Protestant influence was subsequently pushed back after the Tumult of Thorn of 1724. Late modern period (from 1793) After the Second Partition of Poland in 1793, the city was annexed by Prussia. It was briefly regained by Poles as part of the Duchy of Warsaw in years 1807–1815, even serving as the temporary capital in April and May 1809. During these years the city began to attract a growing Jewish community. In 1809, Toruń was successfully defended by the Poles against the Austrians. After being re-annexed by Prussia in 1815, Toruń was subjected to Germanisation and became a strong center of Polish resistance against such policies. The city's first synagogue was inaugurated in 1847. New Polish institutions were established, such as Towarzystwo Naukowe w Toruniu (Toruń Scientific Society), a major Polish institution in the Prussian Partition of Poland, founded in 1875. In 1976, it was awarded the Commander's Cross with Star of the Order of Polonia Restituta, one of highest Polish decorations. After World War I, Poland declared independence and regained control over the city. In interwar Poland, Toruń was capital of the Pomeranian Voivodeship. World War II During World War II, Germany occupied the city from 7 September 1939 to 1 February 1945. The Einsatzkommando 16 entered the city to commit various crimes against Poles. Under German occupation, local people were subjected to arrests, expulsions, slave labor, deportations to concentration camps and executions, especially the Polish elites as part of the Intelligenzaktion. A group of Polish railwaymen and policemen from Toruń were murdered by the German gendarmerie and Wehrmacht in Gąbin on 19–21 September 1939. Local Poles, including activists, teachers and priests, arrested in