Borussia Dortmund was founded on December 19, 1909, as a soccer club based in Dortmund, North Rhine-Westphalia, Germany. The team's formation was driven by a group of young men dissatisfied with the Catholic Church-sponsored Trinity Youth club they were part of. These 18 young rebels decided to create their own soccer team that would later become Borussia Dortmund (source). The name "Borussia" is derived from the Latin word for Prussian (Preußen), while "Dortmund" refers to the city where it's situated.
In its early years, Borussia Dortmund struggled to make an impact on the soccer scene. Their first major accomplishment came in 1913 when they won their local league championship. However, due to World War I interrupting sports competitions throughout Europe, further progress was stalled.
It wasn't until after World War II that Borussia Dortmund started making waves on a national level. In the 1946-47 season, BVB secured the Oberliga West title - their first regional championship since before WWII (source).
Notable players during this period include August Lenz and Alfred Preissler. Lenz played for BVB from 1924 until his retirement in 1937 and helped guide them through difficult times during Nazi regime control over German football (source). Meanwhile, Preissler represented both BVB and Germany at international level; he scored more than 100 goals for Dortmund between 1946 to1958 and earned the nickname 'der Bomber' (source).