thumb|upright=1.20|HMS Tiger sailing alongside HMS Renown
The battlecruiser was the brainchild of Admiral Sir John ("Jacky") Fisher, the man who had sponsored the construction of the world's first "all big gun" warship, . He visualised a new breed of warship with the armament of a battleship, but faster, lighter, and less heavily armoured. The first three battlecruisers, the , were laid down while Dreadnought was being built in 1906.
This design philosophy was most successful in action when the battlecruisers could use their speed to run down smaller and weaker ships. The best example is the Battle of the Falkland Islands where and sank the German armoured cruisers and almost without damage to themselves, despite numerous hits by the German ships. They were less successful against heavily armoured ships, as was demonstrated by the loss of Invincible, , and during the Battle of Jutland in 1916. All three ships were destroyed by more heavily armoured German battlecruisers, with the British failure to prevent fires or explosions in the gun turrets from reaching the magazines also playing a role in the losses. The Renown and Courageous classes, built during the war, were begun when Admiral Fisher was appointed First Sea Lord for the second time in late 1914. Each of these classes in turn served as the fastest capital ships in the world and were heavily armed with four or six guns, but they paid for their speed and armament by having less armour than battleships. was laid down during the war, but was extensively reworked with more armour based on the experience gained at the Battle of Jutland, and was not completed until after the war.
Following the war, the British planned to build the G3 class, which had the same armament and armour as battleships of the time and were rated as battlecruisers only by comparison to the more heavily armoured and slower battleships also planned. They were cancelled as they exceeded the tonnage limits of the Washington Naval Treaty. Of the first nine battlecruisers, only HMS Tiger survived the Washington Treaty and into the 1930s. The three Courageous-class ships were converted to aircraft carriers during the 1920s and only Repulse, Renown and Hood served in the Second World War as battlecruisers. All three went through substantial refits between the wars. Hood was lost in the battle of the Denmark Strait, Repulse was sunk by Japanese aircraft at the start of the war in the Pacific, and Renown survived the war to be scrapped in 1948.
Key
{| class="wikitable" border="1"
|-
| Main guns
| The number and type of the main battery guns
|-
| Armour
| Waterline belt thickness
|-
| Displacement
| Ship displacement at deep load
|-
| Propulsion
| Number of shafts, type of propulsion system, and top speed in knots
|-
| Service
| The dates work began and finished on the ship and its ultimate fate
|-
| Laid down
| The date the keel began to be assembled
|-
| Commissioned
| The date the ship was commissioned
|}
Invincible class
thumb|right|HMS Inflexible about 1909
The Invincible-class ships were the first battlecruisers in the world. The design resembled that of HMS Dreadnought, but sacrificed armour protection and one gun turret from the main battery for a speed advantage. During the First World War Inflexible and Indomitable participated in the unsuccessful pursuit of the German ships Goeben and Breslau in the Mediterranean. Inflexible was recalled home shortly afterwards, but Indomitable remained off the Dardanelles to bottle up the German ships for the rest of 1914 before returning to the UK. Invincible and Inflexible were sent to the South Atlantic in late 1914 to hunt down the German East Asia Squadron and destroyed it at the Battle of the Falkland Islands. Indomitable participated in the Battle of Dogger Bank in the North Sea in early 1915 while Inflexible was badly damaged during the opening stages of the Dardanelles Campaign. The ships formed the 3rd Battlecruiser Squadron at Jutland where Invincible was destroyed by the explosion of an artillery magazine. The two surviving ships spent the rest of the war conducting patrols of the North Sea, as the High Seas Fleet was forbidden by the Kaiser to risk any more losses. They were put into reserve in early 1919 and sold for scrap on 1 December 1921.
{| class="wikitable"
|- valign="top"|- valign="top"
! align= center rowspan=2 | Ship
! align= center rowspan=2 | Main guns
! align= center rowspan=2 | Armour
! align= center rowspan=2 | Displacement
! align= center rowspan=2 | Propulsion
! align= center colspan=3 | Service
|-valign="top"
! align= center | Laid down
! align= center | Commissioned
! align= center | Fate
|- valign="center"
| align= left |
| align= center rowspan=3 | 8 × 12-inch (305 mm)
| align= center rowspan=3 |
| align= center rowspan=3 |
| align= center rowspan=3 | <br />
| align= center |2 April 1906
| align= center|20 March 1909
|- valign="center"
| align= left |
| align= center | 5 February 1906
They spent most of the war patrolling the North Sea and participated in most of the battles there.
Of the two, only New Zealand was in the United Kingdom when the war began. Indefatigable was in the Mediterranean, where she unsuccessfully pursued the German warships and as they sailed towards Turkey. New Zealand participated in some of the early actions in the North Sea, including the Battle of Heligoland Bight and the inconclusive Scarborough Raid. Indefatigable and New Zealand participated in the Battle of Jutland, where the former was destroyed by a magazine explosion after numerous hits from the battlecruiser . New Zealand patrolled uneventfully after Jutland, watching for the next appearance of the High Seas Fleet. She conducted Admiral Jellicoe on his tour of India and the Dominions after the war. New Zealand was sold for scrap in 1922 to comply with the Washington Naval Treaty.
{| class="wikitable"
|- valign="top"
! align= center rowspan=2 | Ship
! align= center rowspan=2 | Main guns
! align= center rowspan=2 | Armour
! align= center rowspan=2 | Displacement
! align= center rowspan=2 | Propulsion
! align= center colspan=3 | Service
|-valign="top"
! align= center | Laid down
! align= center | Commissioned
! align= center | Fate
|- valign="center"
| align= left |
| align= center rowspan=2 | 8 × 12-inch
|}
Lion class
thumb|right|HMS Lion in 1915
The Lion class, nicknamed the "Splendid Cats", were a significant improvement over their predecessors of the in speed, armament, and armour. The Lion-class ships were faster, exchanged the guns of the older ships for guns, and had a waterline belt thick versus the of the Indefatigables. These improvements were in response to the German , Germany's second class of battlecruisers, which were larger and more powerful than the first British battlecruisers of the Invincible class.
HMS Lion served as the flagship of the Grand Fleet's battlecruisers throughout the First World War, except when she was being refitted or under repair. She sank the German light cruiser during the Battle of Heligoland Bight and served as Vice Admiral Beatty's flagship at the battles of Dogger Bank and Jutland. She was so badly damaged at the first of these battles that she had to be towed back to port by and was under repair for more than two months. During the Battle of Jutland she suffered a serious propellant fire that destroyed one gun turret, which had to be removed and rebuilt while the ship was under repair for several months.
Princess Royal served in the Battle of Heligoland Bight a month after the war began and then was sent to the Caribbean to prevent the East Asia Squadron from using the Panama Canal. After the East Asia Squadron was sunk at the Battle of the Falkland Islands by the two Invincible-class battlecruisers, Princess Royal rejoined the 1st Battlecruiser Squadron. During the Battle of Dogger Bank she scored only a few hits, although one directly crippled the German armoured cruiser , which allowed the enemy vessel to be caught and sunk by the concentrated fire of the British battlecruisers. Shortly afterwards Princess Royal became the flagship of the 1st Battlecruiser Squadron, under the command of Rear Admiral Osmond Brock. She was moderately damaged during the Battle of Jutland and required a month and a half of repairs. Both ships spent the rest of the war on uneventful patrols in the North Sea, although they did provide distant cover during the Second Battle of Heligoland Bight in 1917. In 1920 they were both put into reserve and were sold for scrap a few years later under the terms of the Washington Naval Treaty.
{| class="wikitable"
|- valign="top"
! align= center rowspan=2 | Ship
! align= center rowspan=2 | Main guns
! align= center rowspan=2 | Armour
! align= center rowspan=2 | Displacement
! align= center rowspan=2 | Propulsion
! align= center colspan=3 | Service
|-valign="top"
! align= center | Laid down
! align= center | Commissioned
! align= center | Fate
|- valign="center"
| align= left |HMS Queen Mary
| align= center | 8 × 13.5-inch
| align= center | 4 screws, steam turbines,
Tiger was the oldest battlecruiser retained by the Royal Navy after the tonnage limits of the Washington Naval Treaty came into effect in 1922.
{| class="wikitable"
|- valign="top"
! align= center rowspan=2 | Ship
! align= center rowspan=2 | Main guns
! align= center rowspan=2 | Armour
! align= center rowspan=2 | Displacement
! align= center rowspan=2 | Propulsion
! align= center colspan=3 | Service
|-valign="top"
! align= center | Laid down
! align= center | Commissioned
! align= center | Fate
|- valign="center"
| align= left |HMS Tiger
| align= center | 8 × 13.5-inch
| align= center | 4 screws, steam turbines,<br /> They were the world's fastest capital ships upon completion.
was the only ship of the class to see combat in the First World War when she participated in the Second Battle of Heligoland Bight in 1917. Both ships were reconstructed twice between the wars; their armour protection was increased along with other lesser improvements in the 1920s, while a much more thorough reconstruction was done in the 1930s, especially for . Both ships served during the Second World War; they searched for the in 1939, participated in the Norwegian Campaign of April–June 1940, and searched for the in 1941. Repulse was sunk on 10 December 1941 in the South China Sea off Kuantan, Pahang, by Japanese aircraft.
{| class="wikitable"
|- valign="top"
! align= center rowspan=2 | Ship
! align= center rowspan=2 | Main guns
! align= center rowspan=2 | Armour
! align= center rowspan=2 | Displacement
! align= center rowspan=2 | Propulsion
! align= center colspan=3 | Service
|-valign="top"
! align= center | Laid down
! align= center | Completed
! align= center | Fate
|- valign="center"
| align= left |
| align= center rowspan=2 | 6 × 15-inch (381 mm)
| align= center rowspan=2 |
| align= center rowspan=2 | 4 screws, steam turbines,
| align= center| 20 September 1916 This made them the fastest capital ships in existence, slightly faster than even the Renown-class ships.
The first two ships, and , were commissioned in 1917 and spent the war patrolling the North Sea. They participated in the Second Battle of Heligoland Bight and were present when the High Seas Fleet surrendered a year later. Their half-sister was designed with a pair of guns, the largest guns ever fitted on a ship of the Royal Navy, but was modified during construction to take a flying-off deck and hangar in lieu of her forward turret and barbette. After some patrols in the North Sea her rear turret was removed and another flight deck added. Her aircraft attacked the Zeppelin sheds during the Tondern raid in July 1918. All three ships were laid up after the end of the war, but were rebuilt as aircraft carriers during the 1920s. Glorious and Courageous were sunk early in the Second World War and Furious was sold for scrap in 1948.
{| class="wikitable"
|- valign="top"
! align= center rowspan=2 | Ship
! align= center rowspan=2 | Main guns
! align= center rowspan=2 | Armour
! align= center rowspan=2 | Displacement
! align= center rowspan=2 | Propulsion
! align= center colspan=3 | Service
|-valign="top"
! align= center | Laid down
! align= center | Completed
! align= center | Fate
|- valign="center"
| align= left |
| align= center rowspan=2 | 4 × 15-inch
| align= center rowspan=3 | 4 screws, steam turbines,<br />
| align= center| 28 October 1916
Hood, however, was sufficiently advanced in construction that she was completed in 1920 and immediately became flagship of the Battlecruiser Squadron of the Atlantic Fleet. In 1923–24 Hood, accompanied by Repulse and a number of s, sailed around the world from west to east via the Panama Canal. On 23 April 1937, after the beginning of the Spanish Civil War, she escorted three British merchantmen into Bilbao harbour despite the presence of the Nationalist cruiser that attempted to blockade the port. Hood spent most of the early part of the Second World War patrolling against German commerce raiders and escorting convoys. As flagship of Force H based at Gibraltar, she bombarded French ships during the attack on Mers-el-Kébir. In May 1941 Hood and the battleship were ordered to intercept the German battleship Bismarck and the heavy cruiser as they attempted to break out into the North Atlantic. In the subsequent Battle of the Denmark Strait Hoods aft magazines exploded, sinking her within five minutes of the start of the battle.
{| class="wikitable"
|- valign="top"
! align= center rowspan=2 | Ship
! align= center rowspan=2 | Main guns
! align= center rowspan=2 | Armour
! align= center rowspan=2 | Displacement
! align= center rowspan=2 | Propulsion
! align= center colspan=3 | Service
|-valign="top"
! align= center | Laid down
! align= center | Completed
! align= center | Fate
|- valign="center"
|
| align= center rowspan=4 | 8 × 15-inch (381 mm)
| align= center rowspan=4 | 4 screws, steam turbines,<br />
|align=center rowspan=3 |Cancelled 27 February 1919
|- valign="center"
|
|align=center |16 October 1916
The G3 design was approved by the Board of Admiralty on 12 August 1921. Orders were placed in October and November, but were suspended later in November with the beginning of the Washington Naval Conference, which limited battleship numbers. The orders were cancelled in February 1922 with the ratification of the Washington Naval Treaty, which limited construction to ships of no more than displacement.
{| class="wikitable" width=100%
|- valign="top"
! align= center rowspan=2 | Ship
! align= center rowspan=2 | Main guns
! align= center rowspan=2 | Armour
! align= center rowspan=2 | Displacement
! align= center rowspan=2 | Propulsion
! align= center colspan=2 | Service
|-valign="top"
! align= center | Laid down
! align= center | Fate
|- valign="center"
| align= center |G3 battlecruiser
| align= center | 9 × 16-inch (406 mm)
| align= center |
| align= center |
| align= center | Cancelled February 1922
|}