Ludwigshafen was a major industrial center in Germany, and during World War II it was the center of the chemical industry. The Allies (the U.S. and Britain), following the doctrine of "strategic bombing" targeted it for destruction by hundreds of air raids, after warning all civilians to evacuate.
Ludwigshafencenter was a city of 150,000 population (in 1939) on the Rhine River near Heidelberg. Its two giant I.G. Farben plants, covering 1200 acres and employing 40,000 workers, produced much of Germany's ammonia, synthetic rubber, synthetic oil and other vital chemicals; its railroad yards were also important, and hundreds of smaller shops and factories produced war materials, such as diesel engines for submarines. The city fought back, as the Luftwaffe ringed it with 180 high-powered flak guns and numerous airfields to stop Allied bombers.
With the British flying at night and the Americans during the day, some 13,000 Allied bombers hit the city in 121 separate raids during the war, of which 56 raids succeeded in hitting the Farben plant. Those 56 raids dropped 53,000 bombs each containing 250 to 4,000 pounds of high explosives, plus 2.5 million 4-pound magnesium incendiary bombs. (The bombers also dropped millions of warning leaflets and counterfeit ration coupons). Clouds (or protective smoke) usually covered the target, so "pathfinder" lead planes with the best navigators arrived first and marked the general vicinity with flares, allowing the bombers to unload on the flares. This sort of "area bombing" was not especially accurate: out of 1,700 bombs dropped on January 7, 1944, only 127 hit the Farben plank. On average, 1.4 tons of bombs hit each acre of the Farben complex (but buildings covered only 25% of the ground, so most hit open land).
Bombing accuracy improved with experience; in a January, 1945, raid, 1,000 high explosive bombs and 10,000 incendiaries fell within the factory fences, starting 10 large, 30 medium and 200 small fires. Bombs that missed the factory that day ruined 354 residences and dehoused 1,800 people. The shelter system worked well, for only five people on the ground were killed. By war's end most dwellings were destroyed or damaged; 1,800 people had died, and 3,000 were injured. Local Nazi officials assisted the homeless and tried to incite the residents to hate the Allies.
Most residents were fatalistic or passive, and were instead inclined to blame Berlin for their troubles. Thousands fled to villages or farms, but enough stayed behind to keep producing chemicals and to assist troop transports moving by rail to the battle of the Bulge. When draft calls removed German men, I. G. Farben replaced them with German women, with civilian "volunteers" from France or Italy, and with Polish and Russian prisoners. The foreigners worked to avoid death from starvation; the Nazis treated them brutally, and were negligent about their safety during the air raids. Systematic air attacks began in earnest in early 1944, and reduced production by half that year. Repairs took longer and longer, as spare parts were difficult to find. By December, so much damage had been done to vital utilities that output dropped to nearly zero. Followup raids every week ended production permanently. On March 1, 1945, infantry from Alexander Patch's Seventh Army ended Ludwigshafen's agony by seizing the city and liberating the slave laborers.
- U.S. Strategic Bombing Survey, vol 117. 117 Ludwigshafen-Oppau Worls of IG Farbenindustrie AG, Ludwigshafen, Germany (1947), 434pp