British historian Roger Moorhouse
Marcin Obara/PAP

British historian Roger Moorhouse highlighted on social media on Friday that the date marked the anniversary of Nazi Germany’s 1939 invasion of Poland, which started the Second World War.

“#OTD – 1939, at dawn, German forces launch their all out attack on Poland with #Westerplatte, #Wieluń and Tczew among the first places targeted,” Moorhouse wrote on X. “Soon air raids on the major cities followed and German forces rolled en masse across the frontier. #Poland was fighting for its life. #Poland1939.”

A day earlier, Moorhouse had drawn attention to the anniversary of the so-called ‘Gleiwitz incident,’ known in Poland as the ‘Gliwice provocation’ when on August 31, 1939, a German SS unit dressed in Polish uniforms staged a false-flag attack on a radio station in the German town of Gleiwitz, now the southern Polish town of Gliwice. Hitler later used the attack as a justification for his invasion of Poland.

Moorhouse described Germany’s invasion of Poland in his book ‘First to Fight. The Polish War 1939,’ published in the UK in 2019. In early August, his latest book, ‘The Forgers,’ was released, which details the actions of Polish diplomats in Switzerland who saved Jews during the war by providing them with fake Latin American passports.