Infantry Hallamshire Battalion, York and Lancaster Regiment 147th Infantry Brigade, CO Brigadier H. Wood 1st Battalion, Leicestershire Regiment 1/7th Battalion, Duke of Wellington's Regiment 11th Battalion, Royal Scots Fusiliers Attached Units of the 5th Canadian Armoured Division 11th Armoured Regiment (The Ontario Regiment) 12th Independent Machine Gun Company, Princess Louise Fusiliers Units of the 79th British Armoured Division 617th Assault Squadron, Royal Engineers German forces The German forces in the Netherlands (under Oberbefehlshaber Niederlande commander-in-chief Generaloberst Johannes Blaskowitz) had recently been re-designated Fortress Holland (German: Festung Holland), although this name change had little effect on the units on the ground. The rout of forces the previous year, the formation of ad hoc Kampfgruppe (Battle Groups) and cannibalising of units made it difficult for Allied intelligence to determine German strength north of the Rhine, and it was to remain difficult to ascertain their true strength for several years after the war. Approximately 10,000 troops of the 30th Army Corps were believed to be in the Arnhem–Apeldoorn area, under the command of General der Kavallerie Philipp Kleffel. There were believed to be up to 1,000 men of the 346th Infantry Division, the 858th Grenadier Regiment and other miscellaneous units occupying the Arnhem area, including a divisional battle school, paratroopers and Dutch SS. As well as the natural defence provided by the rivers and the high ground north and west of the city, Arnhem itself had been turned into a strong defensive position after the battle the previous year. On the very day of the opening assault on Arnhem, Heinrich Himmler issued a decree that all cities should be defended at any price, failure to do so being punishable by death. Battle On 11 April, II Corps launched Operation Cannonshot – the crossing of the IJssel further north at Deventer – prior to striking west toward Apeldoorn. On the morning of 12 April Foulkes was informed that the operation was well underway, whereupon he ordered the 49th Division to commence their attack that evening. The whole day was spent bombarding the enemy in Arnhem using artillery and ground attack aircraft. The RAF laid on 36 Spitfire and 83 rocket firing Typhoon sorties to soften up the German positions and the attack was preceded by one of the heaviest artillery barrages ever fired by I Canadian Corps. One field gun battery of eight guns fired 640 rounds in ten minutes (an average rate of