The ship was built by the AG Weser shipyard in Bremen, laid down in 1912, launched in April 1914, and commissioned into active service in January 1915.

She saw significant action at the Battle of Jutland on 31 May – 1 June 1916, where she served as the leader of the torpedo boat flotillas that screened for the I Scouting Group battlecruisers.

These included removing a pair of boilers (but retaining the same top speed), taller masts (to allow the ships to serve as flotilla leaders), and the introduction of a superfiring arrangement of the aft guns.

The ship was initially commanded by Fregattenkapitän (FK—Frigate Captain) Ernst Ewers, until the end of her trials on 10 March, when Kapitän zur See (KzS—Captain at Sea) Widenmann replaced him.

The fleet commander, Admiral Friedrich von Ingenohl, argued the ships would eventually be sunk as well, and that any possible successes for the raiders would not equal the loss of a modern light cruiser or a large passenger liner.

[8] On 21 March, she and the rest of II Scouting Group moved to the Baltic, where they took part in operations to defend the German town of Memel over the following two days.

While the rest of II Scouting Group returned to the North Sea, Regensburg sailed to Kiel, where the remaining work to complete fitting out was done at the Kaiserliche Werft (Imperial Shipyard) there.

On 25 August, Regensburg and the cruiser Pillau bombarded Russian positions on the island of Dagö, including the lighthouse in St. Andreasberg and the signal station on Cap Ristna.

Late in the year, the German navy had begun patrolling for merchant shipping between Britain and Scandinavia in the Skagerrak and the Kattegat, initially using torpedo-boat flotillas.

On 25 March, from the direction of Sylt, British seaplane carriers raided the zeppelin base at Tondern, prompting Regensburg and other vessels to sortie to try to intercept them before they withdrew.

During the operation, Kommodore (Commodore) Ludwig von Reuter temporarily took command of II Scouting Group, flying his flag aboard Regensburg.

For the planned operation, Regensburg, the flagship of Kommodore Paul Heinrich, was assigned to serve as the leader of the torpedo boat flotillas that screened for the battlecruisers of I Scouting Group.

At around 15:30, the cruiser screens of I Scouting Group and the British 1st Battlecruiser Squadron engaged; Regensburg was on the disengaged side of the German formation, but steamed to reach the head of the line of battle.

[13] Having successfully disengaged, Scheer ordered Regensburg to organize three torpedo boat flotillas to make attacks on the British fleet during the night.

The raid resulted in the action of 19 August 1916, an inconclusive clash that left several ships on both sides damaged or sunk by submarines, but no direct fleet encounter.

The failure of the operation (coupled with the action of 19 August) convinced the German naval command to abandon its aggressive fleet strategy.

The British nevertheless intercepted the flotilla, and Heinrich sailed east to come to their aid; the ships assisted the heavily damaged torpedo-boat S50 return to port.

Two days later, she was also transferred from II to IV Scouting Group, but on 16 March, the ship was dry docked at Kaiserliche Werft in Kiel for a thorough overhaul and replacement of her main battery with 15 cm (5.9 in) guns.

They were tasked with replacing the heavy units of the fleet that had just completed Operation Albion, the conquest of the islands in the Gulf of Riga, along with the battleships of I Battle Squadron.

The risk of mines that had come loose in a recent storm, however, prompted the naval command to cancel the mission, and Regensburg and the rest of IV Scouting Group was ordered to return to the North Sea on 31 October.

[19] German attacks on shipping between Britain and Norway, which had begun in late 1917, prompted the Grand Fleet to begin escorting convoys with a detached battle squadron.

This decision presented the Germans with opportunity for which they had been waiting the entire war: a portion of the numerically stronger Grand Fleet was separated and could be isolated and destroyed.

Admirals Scheer and Hipper intended to inflict as much damage as possible on the British navy, in order to secure a better bargaining position for Germany, whatever the cost to the fleet.

On the morning of 27 October, days before the operation was scheduled to begin, Karpf ordered Regensburg's crew to take on a full load of coal and oil.

[23][24] As the mutinies spread, Karpf ordered his ships to be dispersed among the smaller ports in the Baltic, to prevent their crews from being influenced by the mutineers aboard the larger vessels.

When the fleet command learned of the incident, they replaced Karpf with Kommodore Heinrich Rohardt, who set about restoring the ships to seagoing condition.

Regensburg then sailed back to Wilhelmshaven, where on 10 December, she embarked KAdm Ernst Goette, who was Germany's representative to the Allied Armistice Commission.

On 24 June, she was transferred to the Marinestation der Ostsee (Baltic Naval Station), which was commanded by now-KzS Ewers, who on 3 July made Regensburg his flagship.

[35] Strasbourg participated in the Rif War in the mid-1920s; on 7 September 1925, she and the battleship Paris and the cruiser Metz supported a landing of French troops in North Africa.

The ship's bow was not designed to operate in an Arctic environment, and so the crew had to continually fix wood planks to the hull to protect it from the ice.