Prussia's borders have changed over time. It has not always been the exact same place. Mostly, Prussia was a small part of what is today northern Poland. After a small number of Prussian people moved there to live, Germans came to live there too. In 1934, Prussia's borders were with France, Belgium, Luxembourg, the Netherlands, Denmark, and Lithuania. Some parts of Prussia are in eastern Poland. Before 1918, a lot of western Poland was also in Prussia. Between 1795 and 1807, Prussia also controlled Warsaw and most of central Poland.