The Second London Naval Treaty was an international treaty signed as a result of the Second London Naval Disarmament Conference held in London. The conference started on 9 December 1935 and the treaty was signed by the participating nations on 25 March 1936.
The signatories were France, the United States, and most members of the British Commonwealth: Australia, Canada, India, New Zealand, and the United Kingdom (on behalf of itself and "all parts of the British Empire which are not separate Members of the League of Nations"). Two Commonwealth Dominions declined to sign: South Africa and the Irish Free State, [1] the latter because it had no navy. [2] Japan, a signatory of the First London Naval Treaty and already at war on the Asian mainland, withdrew from the conference on 15 January. Italy also declined to sign the treaty, largely as a result of the controversy over its invasion of Abyssinia (Ethiopia); Italy was under sanctions from the League of Nations.
The conference was intended to limit the growth in naval armaments until its expiration in 1942. The absence of Japan (a very significant naval power) prevented agreement on a ceiling on the numbers of warships. The treaty did limit the maximum size of the signatories' ships, and the maximum calibre of the guns which they could carry. First of all, capital ships were restricted to a 35,000 long tons (35,562 t) standard displacement and 14-inch (356 mm) guns. [3] However, a so-called "escalator clause" was included at the urging of American negotiators in case any of the countries that had signed the Washington Naval Treaty refused to adhere to this new limit. This provision allowed the signatory countries of the Second London Treaty—France, the United Kingdom and the United States—to raise the limit from 14-inch guns to 16-inch if Japan or Italy still refused to sign after 1 April 1937. [4]
Also submarines could not be larger than 2,000 tons or have any gun armament of greater than 5.1 inches, light cruisers were restricted to 8,000 tons and 6.1-inch (155 mm) or smaller guns and aircraft carriers were restricted to 23,000 tons. Article 25 however gave the right to depart limitations if any other country authorised, constructed or acquired a capital ship, an aircraft carrier, or a submarine exceeding treaty limits, and if such a departure would be necessary for national security. For this reason, in 1938 the treaty parties agreed on a new displacement limit of 45,000 tons for battleships, the ill-fated battlecruiser already having fallen out of favor.
This London Naval Treaty effectively ended on 1 September 1939 with the beginning of World War II. Even during its brief period of supposed effectiveness, three classes of "treaty" battleships were built or laid down under its limitations, the King George V , North Carolina, and South Dakota classes. The designs of the King George V and North Carolina classes were initiated before the escalator clause was invoked, being intended to be armed with, and protected against, 14-inch guns. The United Kingdom declined to invoke the clause, as redesigning the vessels and developing the proposed 15-inch guns would have delayed construction by 18 months, and since these new battleships were badly needed it was considered prudent to build vessels already finalized with 14-inch guns, even if that meant accepting a reduction in firepower compared to adversaries. The United States invoked the escalator clause after the keels were laid for the two members of the North Carolina class, since the class was designed from the onset to be up-gunned from the original 14-inch main battery with minor modification, so they were completed with 16-inch guns since the United States could afford the delay. However, the completed vessel was an unbalanced battleship since its armor scheme was not proof against its up-gunned main armament, so no further ships of the North Carolina were ordered. The four battleships of the South Dakota class were designed with and protected against 16-inch guns, but maintained a 35,000 ton standard displacement, so this necessitated a shorter hull which made for a compact and cramped ship. No longer limited to the Second London Naval Treaty but still constrained by the need to pass through the Panama Canal, design of the Iowa began in 1938 and its orders were placed in 1939; with improved 16-inch guns and greater speed on a displacement of 45,000 tons.
Article 22 of the 1930 Treaty of London relating to submarine warfare declared international law (the so-called "cruiser rules") applied to submarines as well as to surface vessels. Also, unarmed merchant vessels which did not demonstrate "persistent refusal to stop...or active resistance to visit or search" [5] could not be sunk without the ships' crews and passengers being first delivered to "a place of safety" (for which lifeboats did not qualify, except under particular circumstances). [6] The 1936 treaty confirmed Article 22 of the 1930 treaty remained in force, and "all others Powers [were invited] to express their assent to the rules embodied in this Article". [7] [8] This became known as the London Submarine Protocol, and over thirty-five nations eventually did subscribe to it, including the U.S., Britain, Germany, and Japan. [9] It was this Protocol which was used at the post war Nuremberg Trial of Karl Dönitz for ordering unrestricted submarine warfare. These regulations did not prohibit arming merchantmen, [10] but according to Dönitz, arming them, or having them report contact with submarines (or raiders), made them de facto naval auxiliaries and removed the protection of the cruiser rules. [11] This made restrictions on submarines effectively moot. [12] [ clarification needed ]
At the opening meeting of the conference, the Saorstát delegate made it clear that Saorstát Eireann was participating in it because, by an article of the Treaty of 1930, all the signatories had undertaken to meet in conference before the Treaty of 1930 terminated— that is to say, before December of 1936. The Saorstát Government had made it clear that, in their view, the conference on naval limitations should be confined to naval powers, and that as Saorstát Eireann had no navy and was not working on a naval programme, there was no reason for its participation in the conference other than for the reasons stated.
A cruiser is a type of warship. Modern cruisers are generally the largest ships in a fleet after aircraft carriers and amphibious assault ships, and can usually perform several operational roles from search-and-destroy to ocean escort to sea denial.
The Montana-class was a planned class of battleship for the United States Navy, intended as the successor to the Iowa class. They were to be slower but larger, better armored, and with superior firepower. Five were approved for construction during World War II, but changes in wartime building priorities resulted in their cancellation in favor of continuing production of Essex-class aircraft carriers and Iowa-class battleships before any Montana-class keels were laid.
The Washington Naval Treaty, also known as the Five-Power Treaty, was a treaty signed during 1922 among the major Allies of World War I, which agreed to prevent an arms race by limiting naval construction. It was negotiated at the Washington Naval Conference in Washington, D.C. from November 1921 to February 1922 and signed by the governments of the British Empire, United States, France, Italy, and Japan. It limited the construction of battleships, battlecruisers and aircraft carriers by the signatories. The numbers of other categories of warships, including cruisers, destroyers, and submarines, were not limited by the treaty, but those ships were limited to 10,000 tons displacement each.
A heavy cruiser was a type of cruiser, a naval warship designed for long range and high speed, armed generally with naval guns of roughly 203 mm (8 inches) in calibre, whose design parameters were dictated by the Washington Naval Treaty of 1922 and the London Naval Treaty of 1930. Heavy cruisers were generally larger, more heavily-armed and more heavily-armoured than light cruisers while being smaller, faster, and more lightly-armed and armoured than battlecruisers and battleships. Heavy cruisers were assigned a variety of roles ranging from commerce raiding to serving as 'cruiser-killers,' i.e. hunting and destroying similarly-sized ships.
The London Naval Treaty, officially the Treaty for the Limitation and Reduction of Naval Armament, was an agreement between the United Kingdom, Japan, France, Italy, and the United States that was signed on 22 April 1930. Seeking to address issues not covered in the 1922 Washington Naval Treaty, which had created tonnage limits for each nation's surface warships, the new agreement regulated submarine warfare, further controlled cruisers and destroyers, and limited naval shipbuilding.
The Iowa class was a class of six fast battleships ordered by the United States Navy in 1939 and 1940. They were initially intended to intercept fast capital ships such as the Japanese Kongō class and serve as the "fast wing" of the U.S. battle line. The Iowa class was designed to meet the Second London Naval Treaty's "escalator clause" limit of 45,000-long-ton (45,700 t) standard displacement. Beginning in August 1942, four vessels, Iowa, New Jersey, Missouri, and Wisconsin, were completed; two more, Illinois and Kentucky, were laid down but canceled in 1945 and 1958, respectively, before completion, and both hulls were scrapped in 1958–1959.
The North Carolina class were a pair of fast battleships, North Carolina and Washington, built for the United States Navy in the late 1930s and early 1940s.
The County class was a class of heavy cruisers built for the Royal Navy in the years between the First and Second World Wars. They were the first 'post-war' cruisers constructed for the Royal Navy and were designed within the limits of the Washington Naval Treaty of 1922. Such ships, with a limit of 10,000 tons standard displacement and 8-inch calibre main guns may be referred to as "treaty cruisers".
The Mogami class (最上型) was a ship class of four cruisers built for the Imperial Japanese Navy (IJN) during the 1930s. They were initially classified as light cruisers under the weight and armament restrictions of the London Naval Treaty. After Japan abrogated that agreement, all four ships were rearmed with larger guns and reclassified as heavy cruisers. All participated in World War II and were sunk.
Plan Z was the re-equipment and expansion of the Kriegsmarine ordered by Adolf Hitler in early 1939. The fleet was meant to challenge the naval power of the United Kingdom, and was to be completed by 1948. Development of the plan began in 1938, but it reflected the evolution of the strategic thinking of the Oberkommando der Marine over the two decades following World War I. The plan called for a fleet centered on ten battleships and four aircraft carriers which were intended to battle the Royal Navy. This force would be supplemented with numerous long-range cruisers that would attack British shipping. A relatively small force of U-boats was also stipulated.
The Lion class was a class of six fast battleships designed for the Royal Navy (RN) in the late 1930s. They were a larger, improved version of the preceding King George V class, with 16-inch (406 mm) guns. Only two ships were laid down before the Second World War began in September 1939 and a third was ordered during the war, but their construction was suspended shortly afterwards. The design was modified in light of war experience in 1942, but the two ships already begun were scrapped later in the year.
The Geneva Naval Conference was a conference held to discuss naval arms limitation, held in Geneva, Switzerland, in 1927. The aim of the conference was to extend the existing limits on naval construction which had been agreed in the Washington Naval Treaty. The Washington Treaty had limited the construction of battleships and aircraft carriers, but had not limited the construction of cruisers, destroyers or submarines.
The La Galissonnière-class cruisers were commissioned by the French Navy in the 1930s. They were the last French cruisers completed after 1935, until the completion of De Grasse in 1956. They are considered fast, reliable and successful light cruisers. Two cruisers of this class, Georges Leygues and Montcalm, took part in the defence of Dakar in late September 1940 during World War II. With the cruiser Gloire, they joined the Allied forces after the successful Allied landings in North Africa in November 1942. The three other cruisers of the La Galissonière class, held under Vichy control at Toulon, were scuttled on 27 November 1942.
A fast battleship was a battleship which in concept emphasised speed without undue compromise of either armor or armament. Most of the early World War I-era dreadnought battleships were typically built with low design speeds, so the term "fast battleship" is applied to a design which is considerably faster. The extra speed of a fast battleship was normally required to allow the vessel to carry out additional roles besides taking part in the line of battle, such as escorting aircraft carriers.
The South Dakota class was a group of four fast battleships built by the United States Navy. They were the second class of battleships to be named after the 40th state; the first were designed in the 1920s and canceled under the terms of the Washington Naval Treaty. Four ships comprised the class: South Dakota, Indiana, Massachusetts, and Alabama. They were designed to the same treaty standard displacement limit of 35,000 long tons (35,600 t) as the preceding North Carolina class and had the same main battery of nine 16"/45 caliber Mark 6 guns in three-gun turrets, but were more compact and better protected. The ships can be visually distinguished from the earlier vessels by their single funnel, compared to twin funnels in the North Carolinas.
The Alsace class was a pair of fast battleships planned by the French Navy in the late 1930s in response to German plans to build two H-class battleships after the Second London Naval Treaty collapsed. The Alsace design was based on variants of the Richelieu class, and three proposals were submitted by the design staff. The proposed armament included nine or twelve 380 mm (15 in) guns or nine 406 mm (16 in) guns, but no choice was definitively made before the program ended in mid-1940. According to one pair of historians, logistical considerations—including the size of the 12-gun variant and the introduction of a new shell caliber for the 406 mm version—led the naval command to settle on the nine 380 mm design. But another pair of authors disagree, believing that the difficulty of designing and manufacturing a three-gun turret would have caused prohibitive delays during wartime, making the third, largest variant the most likely to have been built. The ships would have forced the French government to make significant improvements to its harbor and shipyard facilities, as the smaller Richelieus already stretched the limitations of existing shipyards. With construction of the first member of the class scheduled for 1941, the plan was terminated by the German victory in the Battle of France in May–June 1940.
A treaty battleship was a battleship built in the 1920s or 1930s under the terms of one of a number of international treaties governing warship construction. Many of these ships played an active role in the Second World War, but few survived long after it.
The Lexington-class battlecruisers were officially the only class of battlecruiser to ever be ordered by the United States Navy. While these six vessels were requested in 1911 as a reaction to the building by Japan of the Kongō class, the potential use for them in the U.S. Navy came from a series of studies by the Naval War College which stretched over several years and predated the existence of the first battlecruiser, HMS Invincible. The fact they were not approved by Congress at the time of their initial request was due to political, not military considerations.
Two South Carolina-class battleships, also known as the Michigan class, were built for the United States Navy in the early twentieth century. Named South Carolina and Michigan, they were the first American dreadnoughts—powerful warships whose capabilities far outstripped those of the world's older battleships.
The Erie-class gunboats were a class of gunboats built by the United States prior to World War II. The class was designed in 1932, and commissioned into the United States Navy in 1936: Erie (PG-50) and Charleston (PG-51). The Eries had a design speed of 20 knots and a main armament of four 6-inch (152 mm) guns in single mounts with four 1.1-inch (28 mm) quadruple mount anti-aircraft guns.
