The Cöln II class was the last class of small cruisers build in Germany before the end of the war. They were the final development of a class of ships that started with the Bremen class in 1903 and was improved in the following years. A total of 10 ships were ordered, but only two of them, the Cöln II and the Dresden II (named after older small cruisers that were lost in the war) entered service very late in the war. Of the eight other ships, five more were launched, the last one was the Frauenlob II on 16.10.1918. All of the incomplete ships were broken down in the following years.

Constuction of the Rostock II was stopped in December 1918, about 7 monthes before completion. The incomplete ship was sold and scrapped in 1921.