HMS Hyacinth was a corvette of the Royal Navy. She served during the Second World War and achieved three victories over enemy submarines in a highly successful career. Only managed to repeat such success among her sister ships. She went on to serve in the Royal Hellenic Navy as RHNS Apostolis (Greek, Modern (1453-);: ΒΠ Αποστόλης), was returned to the Royal Navy in 1952 and scrapped in the same year.
During the Second World War Hyacinth served in the Eastern Mediterranean where she protected the Palestine coastline and escorted numerous convoys along it. She also took part in the Malta convoys. She was a part of the 10th Corvette Group of the Mediterranean Fleet based in Alexandria together with her sister ships and .
Since Hyacinth spent most of her time in the Mediterranean, without access to British shipyards, she was not retrofitted as many of her class were, and so retained her short forecastle. Another of her distinctive features was a 3-inch gun instead of the usual 4-inch.[1]
On 28 September 1941, Hyacinth attacked and sank the Italian submarine north-west of the port of Jaffa, at 32º19'N, 34º17'E, just off the beach at Tel Aviv.
On 9 July 1942, while escorting a convoy from Jaffa to Beirut Hyacinth attacked, damaged and captured the . The submarine was towed into port, repaired and put into operation with the Hellenic Navy under the name Matrosos (Greek: Ματρώζος) in 1943.
On 12 September 1943, after Italy had capitulated, Hyacinth and the Australian minesweeper sank the, after the submarine had been damaged in an attack by Wellington and Swordfish aircraft.
In 1943, Hyacinth was transferred to the Royal Hellenic Navy, and was renamed Apostolis (Αποστόλης), from Nikolis Apostolis, an admiral of the Greek War of Independence, and served the remainder of the Second World War under the Greek flag.