Operation Windsor was a Canadian offensive launched as part of the Battle of Normandy during the Second World War. Taking place on 4–5 July 1944, the attack was undertaken by the Canadian 3rd Infantry Division in an attempt to capture the Norman town of Carpiquet and the adjacent airfield from German forces. The attack was originally intended to take place during the later stages of Operation Epsom, as a means of protecting the eastern flank of the main assault. It was postponed and launched the following week.
On 4 July 1944, four battalions of the Canadian 3rd Infantry Division attacked Carpiquet in conjunction with flanking attacks by armoured regiments of the Canadian 2nd Armoured Brigade. Although the Canadian 8th Infantry Brigade succeeded in capturing Carpiquet by mid-afternoon, German resistance to the south prevented the airfield from being captured—despite significant Allied armour and air support. The following day, Canadian forces defeated German counterattacks and succeeded in holding Carpiquet in preparation for British attacks on Caen as part of Operation Charnwood.
The historic Norman town of Caen was a major Operation Overlord goal for the British 2nd Army′s I Corps, having landed forces on two Normandy beaches on 6 June 1944 in order to capture the city and Carpiquet area. Although Caen was the initial objective of British forces landing on Sword Beach, German resistance prevented the town from being captured on 6 June 1944; an outcome that had been considered a possibility by 2nd Army's commanding officer. For the next three weeks, positional warfare ensued; both sides attacked and counterattacked for minor tactical advantage on the Anglo-Canadian front.
From 26–30 June, the 2nd Army launched Operation Epsom, using the newly arrived VIII Corps and was designed to outflank Caen and seize the high ground near Bretteville-sur-Laize, south of the town. By the end of the action, VIII Corps had succeeded in advancing six miles through extensive field fortifications, the Germans were able to contain the offensive, after committing their last reserves. Depending on the success of VIII Corps, the Canadian 3rd Infantry Division—supported by the Canadian 2nd Armoured Brigade—was to capture the village and airfield of Carpiquet in an attack codenamed Operation Ottawa; this operation was postponed.
Despite the penetrations to the west of Caen, forces of the I SS Panzer Corps still held positions north and west of Caen. Fortifications on the River Orne and near Carpiquet prevented any further advance toward Caen from the north. Carpiquet—3.5 mi (5.6 km) Northwest of the centre of Caen—became an objective of the Canadian 3rd Infantry Division, under the command of Major-General Rod Keller. The need for additional airfields on the Normandy mainland ensured Carpiquet was a valuable prize for the Allies and an important defensive position for the Germans.
The German defences in and around Carpiquet were formidable, as the position was considered "strategically vital" by both sides. The defences at Carpiquet airfield relied on a 1.2 mi (1.9 km) expanse of level ground, which offered the perfect "killing field" for the defenders. The airfield had been converted into a fortress, employing minefields, field gun and machine gun emplacements manned by the 1st Battalion, 26th SS Panzergrenadier Regiment, an anti-aircraft battery and supported by 15 tanks.
For the attack on Carpiquet, Keller selected the three infantry battalions of the 8th Canadian Infantry Brigade; The Queen's Own Rifles of Canada (QRC), Le Régiment de la Chaudière and The North Shore (New Brunswick) Regiment. Also included were The Royal Winnipeg Rifles (RWR) from the Canadian 7th Infantry Brigade, who would lead the assault. Armoured and machine-gun support was to be provided by Canadian 10th Armoured Regiment (The Fort Garry Horse), The Sherbrooke Fusiliers and the Cameron Highlanders Support Battalion. Additional support was later made available in the form of two squadrons of Hawker Typhoon fighter-bombers and three squadrons of specialized tanks from the British 79th Armoured Division. As a means of adding heavy artillery firepower to the initial bombardment, the 16 in (410 mm) guns of the battleship HMS Rodney would bombard German positions around Carpiquet, some 15 mi (24 km) inland.
Operation Windsor was designed to commence at 05:00 on 4 July—following a bombardment by 21 artillery regiments—with Le Régiment de la Chaudière and The North Shore Regiment attacking Carpiquet while the Sherbrooke Fusiliers protected their northern flank. To the south, The RWR would advance and seize the hangars of Carpiquet airfield. Once the two regiments had captured Carpiquet, the QWR would push through and take control of the airfield's control buildings, its capture would enable further Anglo-Canadian attacks against Caen.
Canadian assault on Carpiquet, 4 July
As dawn broke on 4 July 1944, 21 artillery regiments opened fire on German positions in and around Carpiquet, firing a creeping barrage 1 mi (1.6 km) wide and 400 yd (370 m) deep. At 05:00, two Canadian infantry regiments advanced on Carpiquet, while the Sherbrooke Fusiliers attacked to the north. The Sherbooke Fusiliers' attack succeeded in breaking through the German minefields but the defensive positions of the 26th SS Panzergrenadier Regiment remained intact and continued to fire on advancing infantry of The North Shore Regiment. In the centre, the Chaudières avoided much of the fire directed at The North Shore Regiment as they advanced on Carpiquet. By 06:32, both regiments had reached the outskirts of the town, coming into contact with elements of the 12th SS Panzer Division. As fighting in Carpiquet degenerated into a house-to-house battle of attrition, tanks of the Canadian 10th Armoured Regiment assisted the infantry in gradually overcoming German opposition.
To the south, the RWR advanced slowly towards the airfield, with German mortar fire inflicting many casualties on advancing infantry and armour. It would take the RWR 90 minutes to advance the 1.5 mi (2.4 km) between Marcelet and the airfield hangars. Only with eventual indirect fire support from a squadron of the 10th Armoured Regiment was the RWR able to advance to the airfield. Several Sherman tanks were knocked out, by mid-day the RWR were forced to withdraw halfway toward their original positions.
Unaware that the RWR had failed to gain control of the airfield, Keller elected to commit the QRC to the second phase of the assault plan. The regiment moved forward into Carpiquet, now controlled by the Chaudières and The North Shore, who attacked German strongpoints bypassed by the initial assault. It took a combination of infantry attacks, flame-throwers, petard-tanks (Churchill tanks mounted with a 290 mm (11 in) spigot mortar) and the immolation of one strongpoint to force the remaining 12 defenders to surrender, with the rest surrendering after vicious fighting. The QRC reached the edge of Carpiquet as the RWR was withdrawing and was ordered to hold their positions until the RWR could reorganize for a second attack.
For the second attack on the airfield, Keller secured the assistance of two squadrons of Hawker Typhoon fighter-bombers to support the attacks against 12th SS positions. The survivors of the RWR were ordered to "execute a sweeping attack by the lower ground around the enemy's left flank", with full armour and artillery support. In the late afternoon, the RWR resumed the attack on the airfield, although they reached the hangars, they were unable to dislodge the German defenders. Facing counter-attacks by Panzer units, the RWR was ordered to withdraw to their start-line under the cover of darkness. In Carpiquet, three battalions of the 8th Canadian Infantry Brigade rapidly fortified their positions. Following their seizure of the town, the 8th Brigade was now positioned closer to Caen than any other Anglo-Canadian unit. Although the Canadians had firm control of Carpiquet and the northern hangars, the southern hangars and control buildings remained in German hands.
German counterattacks, 5 July
Less than 1 mile (1.6 km) away from the outskirts of Caen, the 8th Canadian Infantry Brigade posed a threat to German positions in the town. With most of the defence concentrated north of Caen and by the River Odon, it was feared that Anglo-Canadian forces could attack from Carpiquet and bypass the majority of the defences. Despite growing misgivings about the success of a counterattack, Kurt Meyer ordered the SS to retake Carpiquet from the Canadians. Units from the 1st SS Panzer division prepared to counterattack at Carpiquet from Francqueville with armour, artillery, mortars and infantry.
Shortly after midnight, the first of the SS counterattacks began, throwing itself against the Canadian defences. Although 13 tanks had been lost the previous day, the remainder of the 10th Canadian Armoured Regiment, supported by mortars from the Cameron Highlanders, prevented German panzers from penetrating the ruins of Carpiquet. Canadian defensive positions and machine-gun fire caused heavy German casualties. By dawn, almost no ground had been gained by the attackers. By midday, the 8th Canadian Infantry Brigade and 10th Canadian Armoured Regiment had defeated three counterattacks with artillery and Hawker Typhoon assistance, ensuring that German forces could not breach the Canadian positions. The town remained under Canadian control, even though German Nebelwerfer Rocket-Artillery and mortars continued to bombard Carpiquet.
Three days after Operation Windsor, attacks on Caen were renewed, with the 3rd Canadian Infantry Division taking part in Operation Charnwood. On 9 July, the 8th Canadian Infantry Brigade succeeded in capturing Carpiquet airfield, as 450 aircraft of the Royal Air Force bombed Caen in preparation for a full assault. By day's end, the northern half of Caen had been seized by British forces, while the remainder of the city had been levelled. On 18 July British and Canadian forces launched Operations Atlantic and Goodwood, the Canadians launched the former operation liberating the remainder of Caen while British forces secured terrain to the east and south of the city. Canadian forces then attacked German positions on Verrières Ridge.
Canadian casualties for the operation totaled 377, of which 127 were fatal. The majority of these losses occurred on 4 July— the RWR and The North Shore Regiment took approximately 130 casualties each on the first day. In total, 17 tanks were lost by the 10th Canadian Armoured Regiment, with an unknown number of losses by the Sherbrooke Fusiliers. Casualty statistics for the 12th SS (Panzergrenadierregiment 26, 1st battalion) indicate 155 total infantry losses,; the 1st SS Panzer division (Leibstandarte Adolf Hitler), responsible for the counter-attack on July 5, lost approximately 20 tanks. Its infantry (Panzergrenadierregiment 1, 3rd battalion) is also known to have lost 115 men killed, wounded or missing 
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