In this chart you can visualize how the Dow Jones performed during WWII.

The Dow experienced high volatility during WWII. Its lowest point (-29%) was reached on april 1942.
But, surprisingly, the Dow gained 33% in the period between the beginning (September 1, 1949) and the end of the WWII (May 7, 1945).

Source:
United States Holocaust Memorial Museum. “WORLD WAR II TIMELINE.” Holocaust Encyclopedia.
encyclopedia.ushmm.org/content/en/article/world-war-ii-key-dates
DOWdowjoneshowtotradeduringwarMoving AveragesputinrussiaWARwwiii

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