The naval arms race between Britain and Germany to build dreadnought battleships in the early 20th century is the subject of a number of books.

Germany's attempt to build a battleship fleet to match that of the United Kingdom, the dominant naval power of the 20th-century and an island country that depended on seaborne trade for survival, is often listed as a major reason for the enmity between those two countries that led the UK to enter World War I. German leaders desired a navy in proportion to their military and economic strength that could free their overseas trade and colonial empire from dependence on Britain's good will, but such a fleet would inevitably threaten Britain's own trade and empire.

His argument was that every nation that had ruled the waves, from Rome to Great Britain, had prospered and thrived, while those that lacked naval supremacy, such as Hannibal's Carthage or Napoleon's France, had not.

Mahan hypothesised that what Britain had done in building a navy to control the world's sea lanes, others could also do - indeed, must do - if they were to keep up with the race for wealth and empire in the future.

Japan, whose British-trained navy wiped out the Russian fleet at the Battle of Tsushima, helped to reinforce the concept of naval power as the dominant factor in conflict.

Mahan wrote in his book that not only world peace or the empire, but Britain's very survival depended on the Royal Navy ruling the waves.

He believed there were "Five strategic keys to the empire and world economic system: Gibraltar, Alexandria and Suez, Singapore, the Cape of Good Hope, and the Straits of Dover."

Naval technology in World War I was dominated by the newly created dreadnought battleship, with several large turrets of equally sized big guns.

The British designs were armed like their heavier dreadnought cousins, but deliberately lacked armor to save weight in order to improve speed, so that these ships would be able to outgun anything smaller than themselves, and get away from anything larger.

They could operate independently in the open ocean where their speed gave them room to maneuver, or, alternately, as a fast scouting force in front of a larger fleet action.

Defensive mines along coasts made it much more difficult for capital ships to get close enough to conduct coastal bombardment or support attacks.

In 1918 the U.S. Navy with British help laid the North Sea Mine Barrage designed to keep U-boats from slipping into the Atlantic.

Though British tactical success remains a subject of historical debate, Britain accomplished its strategic objective of maintaining the blockade and keeping the main body of the High Seas Fleet in port for the vast majority of the war.

Due to diplomatic and internal political pressure, the campaign was stopped that same year and instead for 1916 submarines attacked commerce under cruiser rules, to moderate success.

Far from being starved into submission, and in stark contrast to the experience of Germany, British civilian nutrition improved, with a rise in the average consumption of meat.

The navy of the Ottoman Empire only sortied out of the Dardanelles once late in the war during the Battle of Imbros, preferring to focus its operations in the Black Sea.

Unlike in the Atlantic, the Aegean saw large scale combat involving the French Navy, which provided most of the support vessels to aid in the invasion of Dardanelles and bombarded Athens in an attempt to secure Greek ascension to the Entente.

The main fleet action came in 1915 when the Triple Entente attempted to knock the Ottoman Empire out of the war entirely by capturing Constantinople and securing allied control over the Dardanelles.

This operation turned into the Battle of Gallipoli and ended in defeat for the Triple Entente, Winston Churchill was subsequently force to resign as First Lord of the Admiralty as a result.

It had been expecting to receive two powerful dreadnoughts fitting out in Britain, but the UK seized the completed Reşadiye and Sultân Osmân-ı Evvel with the outbreak of war with Germany and incorporated them into the Royal Navy.

A continual series of cat and mouse operations ensued for the first two years with both sides' admirals trying to capitalize on their particular tactical strengths in a surprise ambush.

Although the two ships skirmished briefly, neither managed to capitalize on their tactical advantage and the battle ended with Goeben fleeing and Imperatritsa Mariya gamely trying to pursue.

After Admiral Kolchak took command in August 1916, he planned to invigorate the Russian Black Seas Fleet with a series of aggressive actions.

The small Romanian Black Sea Fleet defended the port of Sulina throughout the second half of 1916, causing the sinking of one German submarine.

(See also Romanian Black Sea Fleet during World War I) Despite losing most of their coastline to the Central Powers after the Second Battle of Cobadin in October 1916, the Romanians still managed to keep the mouths of the Danube and the Danube Delta under their control, due to the combined actions of their riverine flotilla of four monitors[9] and the protected cruiser Elisabeta, based at Sulina.

The first attack took place on 30 September 1916, when the Romanian torpedo boat Smeul engaged the German submarine UB-42 near Sulina, damaging her periscope and conning tower and forcing her to retreat.

[20] In the Baltic Sea, Germany and Russia were the main combatants, with a number of British submarines sailing through the Kattegat to assist the Russians.

A major coup for the Allied forces occurred on August 26, 1914 when as part of a reconnaissance squadron, the light cruiser SMS Magdeburg ran aground in heavy fog in the Gulf of Finland.

This second operation culminated in the one major Baltic action, the battle of Moon Sound at which the Russian battleship Slava was sunk.

A number of German ships stationed overseas at the start of the war engaged in raiding operations in poorly defended seas, such as SMS Emden, which raided into the Indian Ocean, sinking or capturing thirty Allied merchant ships and warships, bombarding Madras and Penang, and destroying a radio relay on the Cocos Islands before being sunk there by HMAS Sydney.