Nassau-class battleship

SMS Rheinland in 1910
Class overview
Name	Nassau
Operators	Imperial German Navy
Preceded by	Deutschland class
Succeeded by	Helgoland class
Built	1907–1910
In commission	1909–1919
Completed	4
Retired	4
Scrapped	4
General characteristics
Type	Dreadnought battleship
Displacement	Normal: 18,873 t (18,575 long tons) Full load: 21,000 t (21,000 long tons)
Length	146.1 m (479 ft 4 in)
Beam	26.9 m (88 ft 3 in)
Draft	8.76 m (28 ft 9 in)
Installed power	12 × water-tube boilers 22,000 metric horsepower (22,000 ihp)
Propulsion	3 × triple-expansion steam engines 3 × screw propellers
Speed	Design: 19 knots (35 km/h; 22 mph) Maximum: 20.2 knots (37.4 km/h; 23.2 mph)
Range	At 12 knots (22 km/h; 14 mph): 8,300 nmi (15,400 km; 9,600 mi)
Complement	40 officers 968 men
Armament	12 × 28 cm (11 in) L/45 guns 12 × 15 cm (5.9 in) SK L/45 guns 16 × 8.8 cm (3.5 in) SK L/45 guns 6 × 45 cm (17.7 in) torpedo tubes
Armor	Belt: 30 cm (11.8 in) Turrets: 28 cm Battery: 16 cm (6.3 in) Conning Tower: 40 cm (15.7 in) Torpedo bulkhead: 3 cm (1.2 in)

The Nassau class was a group of four dreadnought battleships built for the German Kaiserliche Marine (Imperial Navy) in the early 1900s. The class comprised Nassau, the lead ship, Rheinland, Posen, and Westfalen. All four ships were laid down in mid-1907, and completed by late 1910. Though commonly perceived as having been built in response to the British Dreadnought, their design traces its origin to 1903; they were in fact a response to Dreadnought's predecessors of the Lord Nelson class. The Nassaus adopted a main battery of twelve 28 cm (11 in) guns in six twin-gun turrets in an unusual hexagonal arrangement. Unlike many other dreadnoughts, the Nassau-class ships retained triple-expansion steam engines instead of more powerful steam turbines.

After entering service, the Nassau-class ships served as II Division, I Battle Squadron of the High Seas Fleet for the duration of their careers. From 1910 to 1914, the ships participated in the normal peacetime routine of the German fleet, including various squadron exercises, training cruises, and fleet maneuvers every August–September. Following the outbreak of World War I in July 1914, the ships took part in numerous fleet operations intended to isolate and destroy individual elements of the numerically superior British Grand Fleet. These frequently consisted of sailing as distant support to the battlecruisers of I Scouting Group as they raided British coastal towns. These operations culminated in the Battle of Jutland on 31 May – 1 June 1916, where the ships helped to sink the armored cruiser HMS Black Prince.

The ships also saw service in the Baltic Sea against the Russian Empire during the war; Nassau and Posen engaged the Russian pre-dreadnought Slava during the inconclusive Battle of the Gulf of Riga in 1915. Rheinland and Westfalen were sent to Finland to support White Finnish forces in the Finnish Civil War, though Rheinland ran aground and was badly damaged. Following Germany's defeat, all four ships were ceded as war prizes to the victorious Allied powers and broken up in the early 1920s.