In 1745, under the terms of the Treaty of Dresden, Prussia became the legal ruler of Silesia. Bolesławiec once again found itself under foreign rule, this time Prussian. Little changed in the lives of the inhabitants, however. The reconstruction of buildings destroyed as early as the 17th century continued. On the ruins of the burned-out castle (destroyed by fire during the Thirty Years’ War), construction of a church for Evangelicals began in 1752. The damaged crafts sector was also rebuilt. As a result, in 1789 the population exceeded 3,000, reaching the level from before the Thirty Years’ War. The city, however, was completely Germanized, and documents contained no surnames of Polish origin.
The beginning of the 19th century once again brought war. In 1813, French troops retreating under pressure from Russian forces blew up Bolesławiec’s defensive walls and city gates.
The commander of the Russian army, M. L. Kutuzov, also died here in October 1813. Frederick William III founded a monument in gratitude, dedicated to the memory of Napoleon’s great conqueror. Initially, the obelisk stood in the Market Square; in 1893 it was moved to a square near the defensive walls.
Modern strategy demonstrated the uselessness of massive fortifications, so from 1823 the remains of the gates were dismantled and the moat and castle pond were filled in. After part of the defensive walls and grain warehouses had been demolished, a municipal arsenal was built in 1822. In 1857 it was converted into a theater, designed according to the fashions and needs of the time.
In 1845–46, the railway viaduct that still exists today was built. The structure connects the two elevated banks of the Bóbr and, thanks to the use of dressed-stone masonry, forms an interesting and light-looking building despite its enormous size. From 1846, Bolesławiec had a regular railway connection with Zgorzelec; a year earlier, it had obtained such a connection with Wrocław. Crafts continued to develop, especially ceramic production. Craftsmen were somewhat conservative, however, and resisted change. They sought to preserve the privilege of limiting the number of workshops to five. They also wanted to retain the forms long used in the production of vessels. The Prussian government consistently sought to increase the number of workshops, which it achieved in 1759. Against the will of the guild masters, it also opened the way for newcomers from southern Germany. Despite the government’s efforts, however, the forms once adopted remained unchanged.
GRADUALLY, BOLESŁAWIEC CERAMICS became known beyond the borders of Silesia. Potters exported their products to the Prussian provinces, Poland and Russia.
In 1871, after Prussia unified Germany, Bolesławiec, along with all of Silesia, found itself within the borders of the German Empire. The French indemnity obtained by Prussia contributed to the expansion of the city and the development of other branches of industry. At the turn of the 19th and 20th centuries, a linen factory, a large worsted spinning mill, two steam mills and a large water mill were established. Local railway lines were built from Bolesławiec to Nowa Wieś Grodziska in 1906 and to Modła in 1913.
In 1897, the Vocational School of Ceramics was opened. It had an enormous impact on enriching forms and mechanizing work. Ceramic products became the city’s main export. Therefore, when Poland introduced new customs rates in 1924, ceramic plants had to drastically reduce production and seek new markets. Bolesławiec’s exports began to be directed to Scandinavia. Under the Nazis, the government again sought to raise the level of ceramic production. On Göring’s orders, a workers’ cooperative of potters was established to restore the style of earlier products. In 1936, the ceramics industry ranked first among the other occupations (7 potters, 2 artistic stoneware plants and 4 industrial stoneware plants).
Open-pit mines of so-called faience clay also operated in the area. During the interwar period, copper ore was extracted nearby (Lena, Lubichów, Konrad I and Konrad II). In total, more than 1.5 million tons of copper ore were extracted. It underwent complex concentration processes at the copper smelter in Łąka near Bolesławiec and was transported to Hamburg only in that form, where pure metal was obtained through electrolysis.
During the Second World War, the city continued to develop. Certain aircraft parts were manufactured in some ceramic plants.
One of the branches of the Gross-Rosen concentration camp was located in the city. Prisoners worked mainly in copper-ore mines, quarries and open-pit mines.
For more than five centuries, Bolesławiec remained outside the borders of the Polish state (from 1392 to 1945). It was destroyed several times (the Hussite Wars, the Thirty Years’ War, the Napoleonic Wars, and the First and Second World Wars). From a commercial and crafts town under the Piast dynasty, it gradually transformed into a fairly well-industrialized, diversified city. Despite the dominance of ceramics, other branches of production also developed. Yet even in the German state, Bolesławiec remained a small town of only about 20,000 inhabitants on the periphery of the Third Reich.
On 12 February 1945, the city once again became part of the Polish state.