The Bombing War: Europe 1939-1945

The second major city attack occurred in the early stages of the German aggression against the Low Countries and France, which began on 10 May 1940. Part of the plan was to move the right wing of the German Army Group B through the Netherlands using a combination of surprise paratroop attack, air strikes on military targets and a ground assault. The German priority was to seize Dutch airfields and key communication points, which was largely achieved, though at high cost. By 13 May German forces had reached and occupied southern Rotterdam, but were facing stiff resistance around the bridges over the River Maas, running through the centre of the city. The German Eighteenth Army issued orders to General Schmidt’s XXXIX Corps to break Dutch resistance in the city using all means available, since speed was essential for the rest of the campaign plan. Orders were given to carry out air attacks on 14 May against military targets in the area facing the German Army. That morning, following a German threat to destroy the city, the Dutch authorities began negotiating its surrender. A little after noon, Schmidt ordered the air force units to abandon plans for the raid: ‘bombing attack Rotterdam postponed owing to surrender negotiations’.²³

While talks continued, a large number of Heinkel He111s appeared in the sky, flying in two separate formations towards the centre of the city. Schmidt hastily ordered red flares to be fired; ‘for God’s sake,’ he was heard to say, ‘there’ll be a catastrophe’. Half the 100 aircraft saw the flares and turned back, but 57 dropped their load as directed on Dutch army targets in an urban triangle to the north of the river, in the process burning down 2.8 square miles of the defended area and killing, according to the most recent estimate, 850 people.²⁴ Much of the damage was done by fire caused by leaking oil installations after the bombing. At 3.30 that afternoon the city formally surrendered and to avoid further damage and loss of civilian life, the Dutch Army capitulated a day later. In his memoirs the commander of Air Fleet 2, Albert Kesselring, claimed that radio contact with German forces in Rotterdam broke down at midday so that the cancellation order never got through, but the commander of the bombing squadrons involved later gave testimony that the surrender negotiations were known about and that red flares, fired by German forces from an island on the River Maas, were the signal to abandon the raid if negotiations were still being conducted. One group did see the flares; for the other group, heavy smoke from the battle below obscured them.²⁵ There has never been much doubt that the operation against Rotterdam was occasioned by the difficult situation faced by German soldiers in the south of the city as they tried to force the bridges. Like the bombing of Warsaw, the operations against Rotterdam imposed heavy civilian casualties because the Dutch Army chose to defend the area rather than declare it an ‘open city’ or surrender. In both cases substantial damage and death were also caused by artillery fire. Whether or not Göring was attracted to the idea of displaying German air power once again as irresistible and ruthless, which has sometimes been suggested but never proved, the bombing of Rotterdam excited the same kind of extravagant attention as Warsaw. An RAF air-training manual issued in March 1944 described the attack as an unexampled atrocity with 30,000 dead in 30 minutes.²⁶