They were squat ships, both commissioned in 1926, with a relatively heavy armament for their size (three 150mm Krupp guns, the same type and calibre as for the cruisers Java and Sumatra). Their main asset was an advanced fire control system that made them very accurate in bombarding shore targets, as a similar gunboat, Johan Maurits van Nassau, demonstrated in 1940 when she silenced a German battery from a distance of some 10abbr=onNaNabbr=on.
| Name | Laid down | Launched | Commissioned | Decommissioned | |
|---|---|---|---|---|---|
| 13 January 1925 | 15 August 1925 | 25 March 1926 | 16 September 1968 | ||
| 24 December 1924 | 24 August 1925 | 12 April 1926 | 9 June 1985 |
Flores was brought back to the Netherlands at the start of World War II where she patrolled home waters until the Germans invaded in 1940. Slightly damaged, she escaped to Britain and was employed as a coastal escort. Soemba was withdrawn to Colombo in March 1942, before she could be captured or destroyed by the Japanese invasion of the East Indies.Flores and Soemba were united in the Mediterranean Sea and played an active and successful role in the landings in Sicily, Salerno, Anzio, Garigliano, Gaeta and finally, at the beaches of Normandy in June 1944. The ships came under fire from shore based artillery and bombers many times, but survived all attacks, although they incurred damage several times. British war correspondents referred to them as "the terrible twins".
With their guns worn out due to intensive use, the two ships were retired from active duty shortly after the war and used for artillery instruction and as floating barracks. Soemba was converted to a radar training ship, most of her guns removed and enlarged superstructure fitted to house radar equipment and classrooms. On November 10, 1948, Flores and Soemba were awarded the .
Flores was decommissioned in 1968 and Soemba in 1986.