Sumatra was a Java-class light cruiser. The ship history on netherlandsnavy.nl and uboat.net agree that she was laid down at Nederlandse Scheepsbouw Maatschappij in Amsterdam on 15 June 1916, launched on 19 December 1921, and commissioned on 26 May 1926. The class table on the same Dutch site gives her laid down on 15 July 1916 and launched on 29 December 1920. The history and uboat.net are followed. Uboat.net says the British gave her pennant 40 during the war.
She had come home from the Netherlands East Indies in 1938. On 10 and 11 May 1940 she was at Vlissingen and then left for England. In June 1940 she carried Princess Juliana and her daughters from Milford Haven toward Halifax, with the unfinished Jacob van Heemskerck in company. She was back at Tandjong Priok on 9 October 1940 and was decommissioned at Soerabaja on 16 October, needing a long overhaul. Kapitein ter zee Henri Jan Bueninck had her from 29 January 1941. Uboat.net glosses that rank as captain. He was still in command on 7 December 1941, while she lay at Surabaya.
On 27 January 1942 the Dutch history says she was recommissioned at Soerabaja under Commander J. J. L. Willinge. Uboat.net gives his name as Johannes Jacobus Lukas Willinge and his rank as kapitein-luitenant ter zee, glossed commander. The history says she was not ready for battle and was manned mainly with midshipmen, that she could do 15 knots, and that she was soon ordered to Colombo. She arrived at Trincomalee on 15 February 1942 and was assigned to the 5th Cruiser Squadron. On 16 April she left for Portsmouth by way of Bombay. She arrived at Portsmouth on 31 October and was laid up on 6 November. Willinge left on 17 February 1943.
Kapitein-luitenant ter zee Izaac Willem Reijnierse, whom the Dutch history calls Commander I. W. Reijnierse, had her from 17 February 1943 until 10 March 1944. Uboat.net glosses his rank as commander. The spelling on that page is Izaac, not Isaac. Kapitein-luitenant ter zee Heinrich Witte then had her until 30 April 1944. On 29 April the Dutch history says she was transferred to the Royal Navy. On 30 April it says Captain G. H. Sutcliff, RN, took command from Witte. Uboat.net names the officer George Ernest Sutcliff, a retired captain, and starts him on 18 April 1944, which overlaps Witte. The handover used here is 30 April, the date in the ship history. On 9 June 1944 she was expended as a blockship for Gooseberry 5, in a position 147 degrees from the Quistreham light, 4,500 metres off, and sunk in 7.5 metres of water. The Dutch history prints 7,5 metres and the spelling Quistreham. She was not lost in action against Japan. On 14 February 1951 she was sold at auction for scrapping, with some other wrecks.
A note on sources. The recommissioning at Surabaya, the arrival at Trincomalee, the 5th Cruiser Squadron, the passage to Portsmouth and the blockship are the ship history on netherlandsnavy.nl, saved as a digitized copy. Uboat.net agrees the laying-down, launch and commissioning dates used above, pennant 40, and the end of Dutch service. It starts Sutcliff on 18 April 1944 and gives his initials as George Ernest, against the Dutch history's G. H. Sutcliff and 30 April. The class table's July 1916 and December 1920 dates are not used. Command dates other than Sutcliff's start are the uboat.net list. English ranks follow the glosses uboat.net prints in parentheses. The history does not put her in the April 1942 search off Ceylon. She had already been ordered home on 16 April.