Operation Gomorrah burns Hamburg in a self-sustaining firestorm
Foil strips blind German radar for the first time, and the resulting fire generates its own hurricane-force winds
Quick facts
- Location
- Hamburg, Germany
- Duration
- 24-30 July 1943 (8 days, 7 nights)
- Worst night
- 27-28 July 1943
- Peak wind speed in firestorm
- 120-170 mph
- Estimated deaths
- Roughly 34,000 to 40,000 (no exact count exists)
- Housing destroyed or damaged
- About 61 percent of the city
What happened
Operation Gomorrah, a joint RAF night and USAAF daylight bombing campaign against Hamburg, opened on 24 July 1943 after a two-day weather delay, and ran for eight days and seven nights. For the first time, RAF bombers dropped strips of tin foil, codenamed Window, that scattered enough false radar returns to blind German night-fighter controllers and dramatically cut Bomber Command's losses. The most destructive raid came on the night of 27-28 July, when thousands of incendiaries ignited so many fires so quickly that they merged into a self-sustaining firestorm: temperatures climbed past 1,000 degrees Celsius and generated winds of 120 to 170 miles an hour, stronger than most hurricanes, that tore roofs off buildings and pulled people into the flames. No definitive death toll was ever recorded; estimates cluster around 34,000 to 40,000 killed, and roughly 61 percent of Hamburg's housing stock was destroyed or damaged, forcing close to a million of the city's 1.7 million residents to flee.
Why it matters
Gomorrah demonstrated that incendiary bombing on a large enough scale could generate a firestorm that killed independently of where individual bombs actually landed, a discovery Allied planners would draw on again at Dresden and in the firebombing campaign against Japanese cities. The success of Window also showed how a single simple countermeasure could blunt an air defense system that had taken years to build.
How we know
Postwar damage surveys of Hamburg and RAF Bomber Command's own loss records document both the physical destruction and the drop in aircraft losses once Window went into use; the lack of a precise death toll reflects the scale of a firestorm that killed people in collapsed shelters and open streets alike, many bodies never individually recovered.
Sources
- The National WWII Museum. Operation Gomorrah: The First of the Firestorms · Reputable sourcenationalww2museum.org · The domain "nationalww2museum.org" is on our Reputable source registry. · Link is live and its text matches the event's key terms (Jul 2026)
- World History Encyclopedia. Operation Gomorrah: The 1943 Bombing of Hamburg · Reputable sourceworldhistory.org · The domain "worldhistory.org" is on our Reputable source registry. · Link is live and its text matches the event's key terms (Jul 2026)
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