The first few months of the First World War witnessed significant Allied troop movements through the Mediterranean. British forces from the Far East, India and Egypt passed on their way back to Britain; meanwhile Territorial battalions moved in the opposite direction to relieve the regular garrisons in Gibraltar, Malta and the eastern Mediterranean.

Had enemy submarines been active - they did not arrive in the region till April 1915 - these toings and froings would have been far more hazardous. For the moment news blackouts and censorship meant that a thick fog surrounded what was going on; "a blankness enveloped us ... that leaves near objects clear and blots out the rest with baffling completeness", was how it seemed to a long-time English resident in Alexandria.

The Mediterranean was to have a distinctive flavour as a theatre. When Vera Brittain, whose life as a volunteer nurse is described in Testament of Youth, returned to Britain in 1917, she was struck by how London seemed a besieged city compared to an existence amid Malta's "golden-stoned buildings, of turquoise and sapphire seas, of topaz and amethyst skies".

This reflected a rather rosy afterglow in retrospect, yet there certainly was a difference of intensity in the experience of war in northern and southern Europe after 1914, albeit with notable exceptions. It was widely felt that war service in the Mediterranean was an easy billet compared to elsewhere, and this continued to be so throughout the conflict.

The first adjustment towards a more aggressive Allied stance in the Mediterranean came in January 1915 and focused on the Dardanelles. That this was owed to Winston Churchill at the Admiralty is paradoxical. Having once been all for stripping British ships and arms from the Mediterranean, he now became the advocate of doing the opposite.

This arose from an insatiable temperamental opportunism. But it also represents a recurring theme: the Mediterranean as Great Britain's instinctive default position in successive modern conflicts.

The war in northern France had ground to a bloody halt in a matter of months, and the main British and German fleets were stalemated in the North Sea. For Churchill, a believer above all in movement, it was essential to do something somewhere.

The naval victory at the Battle of the Falklands in the south Atlantic during early December meant that outside the North Sea, the oceans had been cleared of a German threat. This released a surplus of smaller and older ships, including light cruisers. These could not have stood up to a potential German battering in the North Sea but against the Turks - that is, in forcing the Dardanelles as the gateway to Constantinople - they might do the trick.

Yet such suggestions attracted harsh criticisms. Admiral Sir John Fisher, First Sea Lord, recalled that old canard, the failed naval attack at the Bosporus in 1807. More fundamental was the view, from which Churchill had strayed but which others stringently maintained, that the Mediterranean was a fatal diversion.

Gradually, however, Churchill got his way, albeit in a qualified and grudging spirit. Kitchener, always "Egyptian" first and last, and now Minister for War, thought that a demonstration, as he cautiously termed it, at the Straits might at least relieve pressure on the Nile.

Others in London and the Foreign Office, for their part, were eager to make some "splash" to maintain Great Britain's wobbling prestige in the East.

But nothing could be done without the concurrence of the "man on the spot". When Churchill asked Admiral Sir Sackville Garden, commanding the Royal Navy in the Aegean, the plain question of whether the Dardanelles could be forced by ships alone, Carden replied that the Straits could not be rushed in one go, but that they "might be forced by extended operations with a large number of ships".

This opinion was not universally shared even in the squadron, but people got carried along by the momentum especially when they were assured that a purely naval attack could always be broken off if things did not look promising.

When the initial attack was launched at the Dardanelles on 19 February 1915 some modest progress was made against the Outer Forts. But as Allied warships pressed into the Narrows, losses mounted. Mutual backbiting started up.

Slurs were made about the tenacity of the trawlers with their fishermen-recruits from Grimsby and Hull, ordered to go in at night under close fire to clear the deadly mines; subsequent comments that the trawlers were asked to do the navy's job "and had enjoyed no more success than if the Navy had been sent to catch fish off Iceland" were sadly apt.

A big frontal assault was attempted on 18 March, resulting in the disabling of HMS Agamemnon and HMS Inflexible, as well as the sinking of their French counterpart, Bouvet, the latter with 639 fatalities - she had "just slithered down as a saucer slithers down the side of a bath".

Subsequently Carden was sent to a desk job in Malta, and his successor, Admiral John de Robec, came down firmly against any further unsupported naval action.

Instead of breaking it off altogether, however, the decision was now made to launch a combined land and sea operation. In agreeing to this General Sir Ian Hamilton at the head of a Mediterranean Expeditionary Force was determined that the army should take the principal role.

On 25 April 1915 a mixed British, Australian and New Zealand force was landed on the tip of the Gallipoli peninsula. They were immediately confined to a narrow stretch of beach and pounded by Turkish gunfire from the cliffs above.

"Dig, dig, dig until you are safe," was Hamilton's order to his soldiers. The Gallipoli trauma had begun.

Getting soldiers to Gallipoli had been messy and often highly inefficient because of shipping shortages, many shuttled between various ports before being dumped in the peninsula.

Moving the wounded out was even more complicated. Many lay for days on the beaches with dirty dressings. A massive hospitalisation effort was launched across the British Mediterranean.

In the first few months of the war there had been no reason in Malta to anticipate such an emergency. On 4 May 1915, however, the first convoy of the distressed arrived, driven in horse-drawn ambulances through Strada Reale.

By the end of that month there were 4,000 patients accommodated following an improvised expansion of eight hospitals. This rose to 10,000 by January 1916.

The badly-wounded were taken from the white hospital ships in barges to the dockside, and lowered by cranes to the nurses waiting with fresh swabs and clean linen. Malta reverted to its historic Hospitaller role - the "Nurse of the Mediterranean", as it was dubbed - and the old Sacra Infermeria of the Knights provided the biggest ward on the island.

Before long, accommodation for patients - afflicted not least by dysentery and enteritis - overflowed into tents. During the war some 1,500 British servicemen were buried on the island, along with those of many other nationalities (in 1921 Crown Prince Hirohito visited Malta to honour the Japanese sailors who died when serving with their nation's cruisers under British command after 1916).

Although tensions in the Anglo-French naval relationship in the wartime Mediterranean remained muted for some time, there was a natural tendency for them to reappear as time went by.

One problem was that the command structure was confusing and apt to lead to mutual misunderstanding. Apart from nominal supreme command in the Mediterranean, based at Malta, the French had control of waters between France and Algeria, around Toulon, south and west of Greece, and the eastern Mediterranean around Cyprus and off the Syrian coast; while the British controlled zones around Gibraltar, between Malta and Egypt, and in the Aegean.

Not only did French overall command in the region become increasingly vestigial, the British zones showed a natural tendency to expand.

This was partly because of the nature of the maritime war. In August 1914 it seemed that capital warships would be the key to victory, and, so far as the Mediterranean was concerned, France had most vessels in that category.

But no big naval action ever took place (the handful of major Habsburg units never daring to leave the Adriatic), and in anti-submarine work, and keeping military and commercial traffic on the move, the real key lay in the possession of smaller and more flexible ships. The British had far more of these and the gap widened after 1916.

As a result, a feeling grew among the British that they were carrying out the "business part" of the war in the Mediterranean, and this fuelled a desire to regain the independence of action, even primacy, that had been enjoyed before 1914.

The position of the French Commander-in-Chief in the Mediterranean was not enviable. Admiral Lapeyrere, occupying that post after August 1914, soon started spending more time in Bizerte, indisputably French, and as little as possible in Malta.

His successor after late 1915, Admiral Dartige du Fourmet, was forced to remain largely in Valletta, because it was here that information was coming in from the Adriatic and Balkans.

The trouble was that, whatever Churchill may once have said to French Admirals about treating it as their own, Malta remained very British indeed. There were more than 50 Royal Navy ships in and out of the Grand Harbour every day.

Soon du Fourmet felt that his supreme Allied title had become "only a word". It was a relief when he was able to move his command to Corfu in early 1916.

After that the British and the French began to go their separate ways, within the exigencies of alliance. British control over the routing of traffic to avoid the threat from submarines, a task necessarily centralised in Malta, accentuated the divergence.

Here was the background to the reinstatement of the post of "British Commander-in-Chief, Mediterranean", abolished at the outbreak of the war, but renewed during August 1917 in the person of Admiral Sir Somerset Gough-Calthorpe. Technically the latter still reported to du Fournet's successor, Vice-Admiral Dominique Marie Gaucher in Corfu Town, but this was merely nominal.

Gough-Calthorpe's main task to start with was to preside over the introduction of a system of convoys, belatedly introduced as anti-submarine protection. This method generally worked much better in the Atlantic than in the Mediterranean, because there the combination of co-ordination, timing and the greater space available was in its favour. Nevertheless, in the Mediterranean, too, a reduction of losses to U-boat attacks was effected, though they were never eliminated (the greatest number of sinkings came in spring 1917).

Thereafter the British appointed shipping control officers in many Mediterranean ports, again stirring memories of the blockade and supervision of Napoleonic times and their petty annoyances.

Most of the spokes in this wheel went back to naval headquarters in Valletta. It was another way that British power in the region enjoyed a reinvigoration, though detailed oversight from Valletta was not always welcome even to British naval commanders elsewhere in the Mediterranean who in many cases had actually enjoyed having a French supreme commander who could be blithely ignored whenever it suited them.

Malta's own war was defined by hospitals and the comings and goings of navies. Vera Brittain's letters home from the island were "full of wrecks and drowning", recalling, for example, how the loss in the Aegean of the hospital ship Britannic - a vessel that had been a frequent visitor to the Grand Harbour - in late November 1916 "galvanised the island like an electric shock".