The operation was part of the wider Battle of the Scheldt and involved two assault landings from the sea by the 4th Special Service Brigade and the 52nd (Lowland) Division.

While 21st Army Group's priority was then Operation Market Garden, no sense of urgency was placed in securing the approaches to the port facilities there.

Because of this delay, the remnants of the 15th Army "had been given the time to escape and reinforce the island of Walcheren and the South Beveland Peninsula".

The First Canadian Army advanced north-west from the bridgehead in Antwerp and, after heavy fighting in early and mid-October, broke out onto the narrow isthmus which connected South Beveland to the mainland.

A three-pronged assault was planned with British Commandos and part of the 52nd (Lowland) Division landing at Westkapelle in the west of the island and at Flushing in the south.

Against much scepticism and opposition, the plan of Lieutenant General Guy Simonds (acting commander of First Canadian Army) to breach the island's dykes, and flood the interior, was adopted.

The plan to flood the island by bombing breaches in the dykes at Westkapelle, Flushing, and Veere, was controversial from the start.

Simonds, the main protagonist, thought that it would enable the attackers to approach the German positions from both the sea and the inundated-inland sides with landing craft.

But the Canadian engineer, Brigadier G. Walsh, who advised upon the matter pointed out that the breach would be too shallow for landing craft to pass through.

[6] The Germans had installed defences on the dykes to virtually turn them into a continuous fortification bristling with guns of every calibre.

The Royal Marine Commandos were to seize the shoulders of the gap in the dyke and then to fan out north and south to roll up the remainder of the German defences by linking up with the southern thrust.

They split up and were attached to other fighting units where, in the case of some officers and men, their native language skills helped Allied liaison with the local population, while others fought alongside their comrades in arms.

[12] On the day of the assault a heavy mist over Dutch and Belgian airfields limited RAF support for the actual landings, although the skies over Walcheren itself were clear.

The main body came in at 06:30 hours, but by this time the Germans were alert and opened heavy fire with machine guns and 20 mm anti-aircraft cannon.

Nevertheless, the Commandos got ashore with only a few casualties, although the Landing Craft Assaults (LCAs) containing the heavier equipment, including 3-inch mortars, hit a stake and sank some 20 yards (20 m) offshore.

However, they were aided when the leading battalion of 155 Infantry Brigade began to land at 08:30 hours despite having lost two LCAs to heavy fire from one of the coastal batteries.

41 (Royal Marine) Commando, under Lt-Colonel E C E Palmer RM, to land on the north shoulder of the gap blown in the dyke with the objective of clearing the area between there and the village of Westkapelle.

[13] Part of the naval Support Squadron of 27 small craft, under Commanders Sellar and Leefe, closed to engage the eleven still-operational German shore-based batteries, on the direction of Captain A.F.

By 12.30pm, nine of the Support Squadron's craft had been sunk, eleven put out of action, and a high percentage of their crews killed or wounded.

[14][15] In a tribute to the bravery of the Support Squadron, General Robert Laycock, Chief of Combined Operations, wrote to Captain A.F.

4 Special Service Brigade at Walcheren was due largely to the efforts of the Naval Support Craft who, at great cost to themselves, effectively silenced the coastal defences.

Of particular note were the actions of Leading Seaman Owen Joseph McGrath who was Coxswain of a Landing Craft (LCP(L) 144) during the assault on Westkapelle.

[16][17] Back on the island of Walcheren, 41 Commando overran a pillbox in their path and pushed on into Westkapelle where they were met by a battery of four 94 mm (3.7 in) guns.

Corporal Lafont was on the point of breaching the strongpoint with a made-up charge at the ready when the German defenders surrendered.

After landing in a gap in the dyke, about which little was known, Lt-Colonel Dawson asked Brigadier Leicester for a break of some 24 hours to rest his men.

10 cleared Domburg, with the Commando's Norwegian Troop showing particular courage in the face of heavy opposition which cost them a number of casualties.

41 assaulted the last remaining battery, W19, No.4 cleared the Overduin woods and pushed on to Vrouwenpolder opposite North Beveland.

[19][5]: 15–16 Attempts to close the breaches already started in November 1944, but lack of building materials, and of heavy construction equipment, and the destroyed infrastructure, together with the extensive minefields, hampered these efforts.

Therefore, surplus caissons that had not been needed to form the Phoenix breakwaters of the Mulberry harbours were used to block the deepest part of the breaches, after which normal dyke-building operations could proceed.

This made it possible to slowly drain the main mass of water through the locks at Veere and Flushing by opening them at ebb tide.