The Japanese called them "Type D" coast defence ships, and they were the sixth class of Kaibōkan (Kai = sea, ocean, Bo = defence, Kan = ship), a name used to denote a multi-purpose vessel.

The Type D, like the Ukuru and Mikura classes, were dedicated to the anti-aircraft (AA) and anti-submarine role.

The plan was to build a basic escort ship of around 800 tons, with a simple design for easy construction.

The design work for the Type D ships started in March 1943, at the same time as for the Ukuru class.

The lead ship, No.2 (CD-2) was constructed at Yokosuka Naval Arsenal, laid down on 5 October 1943, launched on 30 December 1943, and completed on 28 February 1944.

[3] CD-204 was the last of the class being laid down on 27 February 1945 at the Nagasaki shipyard of Mitsubishi Heavy Industries, launched on 14 April 1945, and completed on 11 July 1945.

The remaining 57 Type D vessels were intended to be built under the 1944 Fiscal Year, but no contracts were ever issued.