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, its clauses were honoured more in the breach than in the observance.[ citation needed ] Three classes of "treaty" battleships were built or laid down by the United States: the North Carolina, South Dakota, and Iowa classes. The design of the North Carolina class was initiated before the escalator clause was invoked, Its ships being intended to be armed with, and protected against, 14-inch guns. However, with the invocation of the escalator clause, they were completed with 16-inch guns. 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. Design of the Iowa-class began in 1938 and its orders were placed in 1939; with the invocation of the "escalator clause", the Iowas carried 16-inch guns 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.
The Montana-class battleships were planned as successors of the Iowa class for the United States Navy, 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".
Unrestricted submarine warfare is a type of naval warfare in which submarines sink merchant ships such as freighters and tankers without warning. The use of unrestricted submarine warfare has had significant impacts on international relations in regards to both the First World War and the Second World War. Its history has been dominated by German decision making.
Myōkō (妙高) was the lead ship of the four-member Myōkō class of heavy cruisers of the Imperial Japanese Navy (IJN), which were active in World War II. She was named after Mount Myōkō in Niigata Prefecture. The other ships of the class were Nachi, Ashigara, and Haguro.
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.
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.
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 Tosa-class battleships were two dreadnoughts ordered as part of the "Eight-Eight" fleet for the Imperial Japanese Navy (IJN) during the early 1920s. The ships were larger versions of the preceding Nagato class, and carried an additional 41-centimeter (16.1 in) twin-gun turret. The design for the class served as a basis for the Amagi-class battlecruisers.
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.
Allied submarines were used extensively during the Pacific War and were a key contributor to the defeat of the Empire of Japan.
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.
A cruiser submarine was a very large submarine designed to remain at sea for extended periods in areas distant from base facilities. Their role was analogous to surface cruisers; 'cruising' distant waters, commerce raiding, and otherwise operating independently. When operating within a fleet, cruisers and cruiser submarines could be expected to scout for and screen the battle fleet. Cruiser submarines were successful for a brief period of World War I, but were less successful than smaller submarines during World War II. Large submarines remained vulnerable to damage from defensively equipped merchant ships (DEMS), were slow to dive if found by aircraft, offered a large sonar echo surface, and were less able to defensively maneuver during depth charge attacks.
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.
