In 1871 the Province of Posen, along with the rest of the Kingdom of Prussia, became part of the newly formed German Empire.
In the mid-19th century, the arrival of the Prussian Eastern Railway (Preußische Ostbahn) contributed greatly to the development of Bromberg.
After the war only 94 houses were inhabited, 103 stood empty and 35 were burned down. The Treaty of Bromberg, agreed in 1657 by King John II Casimir Vasa of Poland and Elector Frederick William II of Brandenburg-Prussia, created a military alliance between Poland and Prussia while marking the withdrawal of Prussia from its alliance with Sweden.
In 1772, in the First Partition of Poland, Bydgoszcz was acquired by the Kingdom of Prussia, renamed Bromberg, and incorporated into the Netze District in West Prussia.
King Casimir III of Poland, granted Bydgoszcz city rights (charter) on 19 April 1346.