Bromberg was the northern of two administrative districts (German: Regierungsbezirk, Polish:Rejencja, ) of the Province of Posen (1849-1918) by the Prussian administration and its predecessor the semi-autonomous Grand Duchy of Poznan (1815-1849). The administrative center was in the city of Bromberg (modern-day Bydgoszcz).
It was bordered on the south by the Posen district, to the west by Brandenburg, to the north and northeast by West Prussia (German: Westpreußen) and to the east by Congress Poland (in borders of Russia).
Bromberg district had a larger percentage of German settlers, and was therefore more Protestant, than average for the Province of Posen. However, the majority of population were Poles and Catholics. Initially, there was a sizeable Jewish minority, but that number diminished over time due to the Ostflucht.
Note: Prussian provinces were subdivided into units called "Kreise" (singular "Kreis", abbreviated "Kr.", English "circle"), which were similar to large counties in US terms. Cities would have their own "Stadtkreis" (English: "municipal county") and the surrounding rural area would be named for the city, but referred to as a "Landkreis" (English: "rural county"). In the case of Posen, the Landkreis was split into two: Landkreis Posen West, and Landkreis Posen East. (Data is from Prussian censuses, during a period state-sponsored 'germanization', and includes military garrisons.) The district was originally divided into several larger Kreise, which were later divided into the final 13 Kreise, the larger ones spinning off smaller units.