'Ambassador' was a British special forces raid by H Troop of No. 3 Commando and No. 11 Independent Company on the island of Guernsey in the Channel Islands group (14/15 July 1940).

As a result of a series of mishaps, ill luck and the haste with which the undertaking was planned and implemented, the raid resulted in no immediate military gains for the British, although the experience gained in the mounting and conduct of the operation was to prove invaluable for the success of subsequent commando operations.

On 30 June 1940 and following the surrender of France, the Germans landed troops in the Channel islands group in Grünpfeil'. Two days later, Prime Minister Winston Churchill sent a memo to his chief staff officer, Major General H. L. Ismay, requesting the start of planning for a raid on the islands as soon as possible, and stating that he felt that it would be the type of operations suitable for implementation by the newly formed commando units. Matters began move very quickly, and the War Office approved the proposal for an operation later in that same day. Shortly after that, the planning process began in earnest.

It was decided that the resulting 'Ambassador' operation would follow two preliminary operations codenamed 'Anger'. These preliminary operations were to be undertaken in order to gather the intelligence needed before a raid by 140 men, who were to land on the island of Guernsey and attack the airfield with the purpose of destroying aircraft and buildings, as well as capturing or killing members of the garrison. The units selected for the raid were 'H' Troop of No. 3 Commando and No. 11 Independent Company. No. 3 Commando, under the command of Lieutenant Colonel John Durnford-Slater, had only just been raised (it completed its recruitment on 5 July), and had not yet begun training, while No. 11 Independent Company, under the command of Major Ronnie Tod, had been raised earlier in June and had a few weeks earlier undertaken 'Collar', which had been a hastily organised and largely unsuccessful raid on Boulogne. During the planning stage of 'Ambassador', Durnford-Slater went to London, where he worked out most of the details with David Niven, who was then serving as a staff officer in the Combined Operations Headquarters.

On the night of 7/8 July a reconnaissance operation was carried out, when Lieutenant Hubert Nicolle, an officer in the Hampshire Regiment who was originally from Guernsey and first commissioned in the Royal Guernsey Militia, was landed on the island by the submarine H 43. Nicolle was recovered three days later, and on the basis of the information he provided it was determined that the garrison on Guernsey comprised of 469 German soldiers, concentrated mainly around St Peter Port, and although there were machine gun posts along the coast, these were sited in a manner that meant that it would take some 20 minutes between the raising of the alarm and the despatch of reinforcements.

The original plan had been for the raid to be carried out on the night of 12/13 July, but at the last moment it was put back to 14/15 July. Even then, shortly before embarkation, Durnford-Slater received intelligence that the Germans had reinforced a number of the places where it had been planned to land some of the parties, so the plan was perforce changed at the last moment. After the details had been fixed, final preparations were undertaken in the gymnasium at the Royal Naval College, Dartmouth, where some of the cadets helped the commandos with loading magazines and helping prepare the Bren light machine guns and Thompson sub-machine guns that had been brought down from London specifically for the operation.

At 17.45 the raiding force embarked in the destroyers Scimitar and Saladin, and accompanied by six Royal Air Force air/sea rescue launches that were to transfer the men from the destroyers to the landing beaches, departed for Guernsey. As a consequence of the loud noise of the RAF launches' engines, it was arranged that Avro Anson general reconnaissance aircraft would overfly the island to disguise the sound of the engines.

Under the plan that he had generated, Durnford-Slater had the men of the independent company attack the airfield and the commandos create a diversion. To this end, three landing points were selected: in the end, however, only the diversionary force from No. 3 Commando, comprising a mere 40 men, was able to land successfully, in this instance at a beach in Telegraph Bay just to the west of the Jerbourg peninsula, at 00.50 on 15 July, despite a faulty compass on the launch carrying them ashore.

One party of No. 11 Independent Company was taken to the wrong island, Sark, as a result of another faulty compass. Landing on Little Sark, the team explored La Sablonnerie and, not finding any Germans, returned safely to the destroyer. Another party crashed into a rock and the other two launches broke down after experiencing a series of technical problems.

Soaked to the skin as they landed, the men of No. 3 Commando failed to find any of the 469-man German garrison: the men located a German barracks and a machine gun position, but both of these had been abandoned before the arrival of the British party. One islander was encountered, but this man had a speech impediment and was knocked unconscious to keep him quiet. The men of the party demolished a loose garden wall to make a small road block. Not hearing any noise from the direction of the airfield, the men decided to effect a stealthy retreat. The rendezvous with the destroyers that were recovering them was 03.00, and if they were late the destroyers were under orders to leave them behind, so the party subsequently returned to the beach, stopping to cut a couple of telegraph lines on the way. Arriving at the landing beach, the raiders discovered that they had to extract themselves by swimming some 100 yards (90 m) out to their boats as the tide had risen too high for the motor launches to beach among the rocks.

It was only at this stage that it was discovered that three of H Troop’s men could not swim, and they had therefore to be left on the beach with additional French currency. Although Durnford-Slater requested that a submarine be sent back for these men, the Admiralty decided that such an effort would be too risky and as a result the men later surrendered. During the extraction, a dinghy was used to ferry weapons to the boats, but on its fifth such excursion it was dashed against a rock and overturned. One of the boat’s two occupants, a soldier, was presumed drowned at the time, although later it was reported that he actually managed to get ashore and was subsequently taken prisoner.

The raid could thus be deemed only as a failure as none of its objectives had been achieved. No casualties had been inflicted on the Germans, no prisoners had been taken, and the only damage caused was the cutting of a telephone line. Additionally, the quality of the planning and the conduct of the operation were later called into question. Much of the equipment used was either not serviceable (faulty compasses and motor launches that broke down) or inadequate for the task demanded of the, and the launches which did work were unable to come all the way into the beach as a result of their draught. Moreover, some of the tasks that had been assigned were impractical or had not been rehearsed (the wire intended for use as a road block was too heavy to be carried from the beach) and the intelligence on the Germans dispositions on the island was at best outdated or completely erroneous. The commandos also found they were burdened with equipment that was not of use: this included steel helmets, gaiters and an excessive quantity of ammunition. This was largely the result of the haste with which the operation had been conceived and then put together, but it was also indicative of the embryonic status of the raiding and commando concept.

In political terms, the raid was also a disaster. Churchill was said to have been furious about the 'comical' way in which the operation had been undertaken, and it has been claimed that for some months the whole commando concept was 'in jeopardy' as the authorities even considered their disbandment, although this did not happen. As a concept, the commandos then went on to perform with considerable success later in the war. Indeed, it has been argued by some, including Durnford-Slater, that the commandos' future success in operations such as 'Neptune' (iii) was in part due to the early failures such as 'Ambassador', from which a host of lessons were learned that proved vital in the planning and implementation of future commando operations.

Even so, the failure of 'Ambassador' led to widespread and indeed fruitful changes. The independent companies were in turn disbanded and their personnel used to raise the first 12 commando units. Much additional work went into the training and planning side of the raiding concept, and for the next eight months the commandos did little except train. To this end formalised training schemes and schools were established, and Churchill sought to invigorate the concept by replacing Major General A. G. B. Bourne as the Director of Combined Operations with Admiral Sir Roger Keyes.