Key Point: Only eight dreadnoughts remain, all in the United States.
The age of the steel line-of-battleship really began in the 1880s, with the construction of a series of warships that could carry and independently aim heavy guns external to the hull. In 1905, HMS Dreadnought brought together an array of innovations in shipbuilding, propulsion, and gunnery to create a new kind of warship, one that could dominate all existing battleships.
Although eventually supplanted by the submarine and the aircraft carrier, the battleship took pride of place in the navies of the first half of the twentieth century. The mythology of of the battleship age often understates how active many of the ships were; both World War I and World War II saw numerous battleship engagements. These are the five most important battles of the dreadnought age.
Battle of Jutland:
In the years prior to World War I, Britain and Germany raced to outbuild each other, resulting in vast fleets of dreadnought battleships. The British won the race, but not by so far that they could ignore the power of the German High Seas Fleet. When war began, the Royal Navy collected most of its modern battleships into the Grand Fleet, based at Scapa Flow.
The High Seas Fleet and the Grand Fleet spared for nearly three years before the main event. In May 1916, Admiral Reinhard Scheer and Admiral John Jellicoe laid dueling traps; Scheer hoped to draw a portion of the Grand Fleet under the guns of the High Seas Fleet, while Jellicoe sought to bring the latter into the jaws of the former. Both succeeded, to a point; British battlecruisers and fast battleships engaged the German line of battle, before the arrival of the whole of the Grand Fleet put German survival in jeopardy.
The two sides fought for most of an afternoon. The Germans has sixteen dreadnought battleships, six pre-dreadnoughts, and five battlecruisers. Against this, the British fielded twenty-eight dreadnoughts and nine battlecruisers. Jellicoe managed to trap the Germans on the wrong side of the Grand Fleet, but in a confused night action most of the German ships passed through the British line, and to safety.