| Black May | |||||||
|---|---|---|---|---|---|---|---|
| Part of The Battle of the Atlantic | |||||||
&sq=Envato&lang=en&file=File:The_Royal_Navy_during_the_Second_World_War_A4570.jpg) Depth charges exploding from the destroyer HMS Vanoc during an Atlantic convoy in May 1943 | |||||||
| |||||||
| Belligerents | |||||||
 United Kingdom Canada |
 Germany | ||||||
| Commanders and leaders | |||||||
 Max Horton John Slessor |
 Karl Dönitz | ||||||
| Strength | |||||||
|
Royal Navy Merchant navy | 240 submarines | ||||||
| Casualties and losses | |||||||
| 58 ships sunk |
43 submarines destroyed 37 submarines damaged | ||||||
Black May refers to a period (May 1943) in the Battle of the Atlantic campaign during World War II, when the German U-boat arm (U-Bootwaffe) suffered high casualties with fewer Allied ships sunk; it is considered a turning point in the Battle of the Atlantic.