Following the Royal Navy's revenge at the Battle of the Falkland Islands a month later, the only surviving German cruiser, SMS Dresden, was finally hunted down and cornered at Más a Tierra early in 1915, where she was scuttled after a brief battle with British cruisers.

The Imperial German Navy's rank and rating system combined that of Prussia's with the navies of other northern states, thus the resulting system became one of Europe's best.

The Royal Navy's blockade of German ports prevented Germany from importing food and hastened German capitulation by creating a food crisis in Germany.

The first works were carried out by the Spanish engineer Raymondo Lorenzo d ' Equevilley Montjustin ( submarine Narval ), who based the German Navy's first U-boat design, on the Russian export models bound for the Russo-Japanese War.

By 1916, after the Battle of Jutland, the Germans were forced to concede that the Imperial German Navy's surface fleet could not challenge the strength of the Royal Navy on the high seas, so great faith was placed in the U-Boat to strangle British supply lines in the Atlantic.

* Mid-1930s to 1939 — commander of the German Navy's sail training ship Albert Leo Schlageter

The Royal Navy's Barracudas made several attacks on the German battleship Tirpitz in 1944.

However, as the Royal Navy's blockade of the German Empire was a critical direct and indirect factor in the eventual German collapse, Mahan's theories were vindicated by the First World War.

During the Second World War the German Navy's submarine fleet of U-boats almost starved Britain into submission and inflicted huge losses on US coastal shipping.

In 1945 the tasks of various predecessor organisations ( among them the German Navy's hydrographic service, the Wilhelmshaven maritime observatory, and the " Deutsche Seewarte " under Georg von Neumayer ) were concentrated in the newly created " Deutsches Hydrographisches Institut " ( DHI ) in Hamburg.

This was the day that Britain's Royal Navy destroyed the German battleship Bismarck after it had sunk the Royal Navy's HMS Hood.

The German Navy's Enigma ciphers were considerably more secure than those of the German Army or Air Force, which had been well penetrated by 1940.

OKM did not take into account the Royal Navy's determination to destroy the German surface fleet.

Early in World War II, Agnes Driscoll was engaged in the U. S. Navy's effort against the German naval Enigma machine, with this work being superseded by the US-UK cryptologic exchanges of 1942-43.

A second opportunity to use the Mistels, in Scapa Flow in 1944, was abandoned after the sinking of the German battleship Tirpitz led to the departure of all the Royal Navy's major surface units from the target.

In 1944, USAAF commander Lt. Gen. Henry (" Hap ") Arnold acquired 2 groups of A-24 dive bombers, the army version of the Navy's SBD-2, in response to the success of the Stuka and German CAS.

The technique is claimed to have been most effective against messages produced by the German Navy's Enigma machines.

In October, 1914, the British also obtained the Imperial German Navy's Handelsschiffsverkehrsbuch ( HVB ), a codebook used by German naval warships, merchantmen, naval zeppelins and U-Boats.

This is in contrast to the US AN / SPY-1 system ( as used on the Ticonderoga class cruiser and Arleigh Burke class destroyer ) or the Dutch / German / Canadian APAR system ( as used on the Royal Dutch Navy's De Zeven Provinciën class frigates, the German Navy's Sachsen class frigates, and the Royal Danish Navy's Ivar Huitfeldt class frigates ), which use multiple arrays fixed in place to provide continuous coverage of the entire sky.

Nearly 3, 700 Allied ships were sunk at a cost of 783 German U-boats.

* 1914 – World War I: First Battle of the Atlantic – two days after the United Kingdom had declared war on Germany over the German invasion of Belgium, ten German U-boats leave their base in Heligoland to attack Royal Navy warships in the North Sea.

A major setback was caused by the German Navy introducing the four-rotor Enigma used for communicating with U-boats.

Italian submarines participated in the Battle of the Atlantic from this base which was also a major base for German U-boats as headquarters of 12th U-boat Flotilla.

The Baralong Incidents were naval engagements of the First World War in August and September 1915, involving the Royal Navy Q-Ship, later renamed HMS Wyandra, and two German U-boats.

* SS Corvus, a Norwegian steamship sunk by German U-boats in February 1945

In April 1917, when German U-boats were sinking many British ships with torpedoes, the marine artist Norman Wilkinson devised dazzle camouflage, which paradoxically made ships more visible but harder to target.

* 1914: German U-boats were powered by MAN diesels.

In the Quirin affair during World War II, German U-boats set two small groups of Nazi agents ashore in Florida and Long Island to cause acts of sabotage within the country.

* 1942 – World War II: Battle of the Atlantic – German Grand Admiral Karl Dönitz orders the last U-boats to withdraw from their United States Atlantic coast positions in response to the effective American convoy system.

During the war, Friedrich Krupp Germaniawerft produced 84 U-boats for the German navy, as well as the Deutschland submarine freighter, intended to ship raw material to Germany despite the blockade.

Friedrich Krupp Germaniawerft shipyard launched the German cruiser Prinz Eugen, as well as many of Germany's U-boats ( 130 between 1934 and 1945 ) using preassembled parts supplied by other Krupp factories in a process similar to the construction of the US liberty ships.

During the Second World War, German U-boats used the currents to pass into the Mediterranean Sea without detection, by maintaining silence with engines off.

In the Gallipoli Campaign in the spring of 1915 in the eastern Mediterranean, German U-boats, notably the U-21, prevented close support of allied troops by 18 pre-Dreadnought battleships by sinking two of them.

This continuous action became known as the Battle of the Atlantic, as the British developed technical defences such as ASDIC and radar, and the German U-boats responded by hunting in what were called " wolfpacks " where multiple submarines would stay close together, making it easier for them to sink a specific target.

The U. S. military engaged in various tactics against German incursions in the Americas ; these included military surveillance of foreign nations in Latin America, particularly in the Caribbean, in order to deter any local governments from supplying German U-boats.

Using newly captured French ports, the German Navy enjoyed success against an over-extended Royal Navy, using U-boats against British shipping in the Atlantic.

Between 1939 and 1945, 3, 500 Allied merchant ships were sunk at a cost of 783 German U-boats.

King — and Canada — were largely ignored by Winston Churchill, despite Canada's major role in supplying food, raw materials, munitions and money to the hard-pressed British economy, training airmen for the Commonwealth, guarding the western half of the North Atlantic Ocean against German U-boats, and providing combat troops for the invasions of Italy, France and Germany in 1943-45.

* July 19 – WWII: Battle of the Atlantic: German Grand Admiral Karl Dönitz orders the last U-boats to withdraw from their United States Atlantic coast positions, in response to an effective American convoy system.

But the German capital ships had been bottled up in the North Sea, and the main threat to shipping came from U-boats.

During this time, German U-boats sank a number of merchant marine ships and three Canadian warships.