The Van Speijk-class frigates were built for the Royal Netherlands Navy in the 1960s. They were versions of the British Leander-class frigates with Dutch radars. The British design was chosen in order to enable rapid construction in order to replace elderly destroyer escorts and take up part of the NATO patrol duties of the decommissioned anti-submarine warfare carrier Karel Doorman. The ships were modernised in the late 1970s. All six ships were sold to the Indonesian Navy in 1986–1989 and five are still in service as the Ahmad Yani-class frigates.

For the most part the Dutch limited their changes to the Leander design to a wholesale replacement of the original British electronics and electrical equipment by those from Dutch manufacturers. Hollandse Signaalapparaten supplied the entire electronics suite. Specifically their LW-02 long-range air-surveillance radar, the DA-02 medium-range air/surface search radar and the M45 combined radar and optical fire control system for the 4.5 in (110 mm) guns. The Dutch HSA M44 radar/visual director for the Seacat anti-aircraft missiles could automatically target in elevation and bearing and because of its much lighter weight, allowed the single Seacat launcher on the British ships to be increased to two launchers on the Dutch ships, each with their own director.^[1]

All ships were named after Dutch naval officers.^[1] When sold to Indonesia, they were named after Indonesian National Armed Forces heroes.

At least some, if not all, of the Indonesian ships have replaced their Seacat launchers with two twin Simbad launchers.^[3] Recently, the two quadruple Harpoon launchers were also replaced by Yakhont missile (SS-N-26) launchers purchased from Russia, because the early version Harpoon missiles previously installed were nearing their obsolescence period. There are also some conflicting reports that the Harpoon missiles were replaced with Chinese-sourced C-802 rather than Russian Yakhont. There are some pictures circulating on the internet showing several vessels of the class carrying box launchers that look much too small to be Yakhont's launchers, but they are the right size for C-802.

Pictures released in March 2011 show that modifications were made to KRI Oswald Siahaan with 4 SS-26 Yakhont VLS cells located in the quarterdeck beside the helicopter hangar.^[4]