Bloody Sunday (1939)

Bloody Sunday (German: Bromberger Blutsonntag; Polish: Krwawa niedziela) was a sequence of violent events that took place in Bydgoszcz (German: Bromberg), a Polish city with a sizable German minority, between 3 and 4 September 1939, during the German invasion of Poland.

Standing in the path of the German army's advance during the early days of the invasion, tensions quickly escalated in Bydgoszcz between the city's sizable German-speaking minority and its Polish majority. On 3 September, as the Wehrmacht was preparing to assault the city, members of the German minority working in conjunction with the German intelligence agency (Abwehr) attacked the Polish garrison. Polish soldiers and civilians reacted with violent reprisals against ethnic Germans, who in turn reacted with more violence. A Polish investigation concluded in 2004 that approximately 40–50 Poles and between 100 and 300 Germans were killed.

The term "Bloody Sunday" was applied to the events by Nazi propaganda officials, who highlighted the German casualties. At worst, the incident had been an overreaction by Poles to collaboration by ethnic Germans, resulting in both Nazi collaborators and innocent civilians being killed in subsequent reprisals. However, Nazi propaganda depicted it as an unprovoked massacre and inflated the death toll to 58,000 victims, as a way to justify future German atrocities against Poles. An instruction issued to the press said, "... must show news on the barbarism of Poles against Germans in Bromberg. The expression 'Bloody Sunday' must enter as a permanent term in the dictionary and circumnavigate the globe. For that reason, this term must be continuously underlined."

Approximately 200–400 Polish hostages were shot in a mass execution in the aftermath of the fall of the city on 5 September. Additionally, fifty Polish prisoners of war from Bydgoszcz were accused by Nazi summary courts of taking part in "Bloody Sunday" and shot. The reprisals compounded violence stemming from the German attempts to pacify the city, and the premeditated murder of notable Poles as part of Operation Tannenberg. As part of the latter, the Germans murdered 1,200–3,000 Polish civilians in Bydgoszcz, in a part of the city that became known as the Valley of Death.