The building contract for Panzerschiff "D" (Ersatz Elsass) was placed with the Marinewerft, Wilhelmshaven (from 1935 the Kriegsmarine Werft) on 25. January 1934. The design had not received final approval though.
The keel was laid on 14 February 1934 on slipway 2. 5 July 1935 the work was stopped and the material scrapped. The original plans had been modified to accommodate the new specifications and a fresh keel was laid down on 15 June 1935.
It was Construction No. 125 at the Kriegsmarine Werft, Wilhelmshaven.
She spent almost 16 months on the ways before she was launched on 3 October 1936. The ship was christened by the widow of Kapitän zur See (Captain) Felix Schultz, commander of the armoured cruiser Scharnhorst, lost with his ship at the Battle of the Falkland Islands on 8 December 1914.
The Scharnhorst was commissioned nearly 27 months later on 7 January 1939 and placed under the command of Kapitän zur See (Captain) Otto Ciliax.
Following the commissioning the ship conducted intensive trials in the Baltic Sea.
On 1 April 1939 the Scharnhorst was at Wilhelmshaven for the launching that day of the new battleship Tirpitz.
The Scharnhorst was the largest unit present and acted as flagship. After the launch of the Tirpitz the promotion of Generaladmiral Erich Raeder to Grossadmiral (Grand Admiral), by Hitler, took place on the quarterdeck of the Scharnhorst.
Preliminary trials in the first half of 1939 indicated that adjustments and alterations were necessary in some systems and equipment, such as the new boilers, and that problems would exist because of the low freeboard and bow trim.
In August 1939 an aircraft hangar was added and the stem was modified as a result of the trials.
Photo: The Scharnhorst during her sea trials after she was modified.
On 2 September 1939 the Scharnhorst made a brief trial run to check out such adjustments and added new features. It was found that some work had to be accomplished on the superheater tubes, as they were not functioning properly.
British bombers raided the German Bight for the first time on 4 September 1939 on an anti-shipping sortie both Scharnhorst and Gneisenau were at Brunsbüttel. At 1803 two two engine bombers flew over the two German battleships at a height of about 1500 meters. The Scharnhorst and Gneisenau responded the attack using their anti-aircraft guns. The British bombers turned away and left the area without dropping their bombs.
Weeks of intensive battle training were conducted in the Baltic before Scharnhorst returned to Wilhelmshaven in November 1939.
The ship was now ready for combat operations.