Andreas du Plessis de Richelieu
Danish naval officer and businessman
Died when: 80 years 30 days (961 months)Star Sign: Pisces

Andreas du Plessis de Richelieu (24 February 1852 – 25 March 1932) was a Danish naval officer and businessman who became a Siamese admiral and minister of the navy.
He was granted the Thai noble title Phraya Chonlayutthayothin (Thai: ???????????????????).He commanded forces at the Phra Chulachomklao Fortress in the Paknam Incident of 13 July 1893, that ended the Franco-Siamese War, and went on to become the first and only foreign-born commander-in-chief of the Royal Thai Navy, from 16 January 1900 to 29 January 1901.
He returned to Denmark in 1902, suffering from malaria.He died at Kokkedal House in Hørsholm and is buried at Holmens Cemetery in Copenhagen.
Botanist Ernst Johannes Schmidt in 1901, circumscribed Richelia, which is a genus of nitrogen-fixing, filamentous, heterocystous and cyanobacteria and named in Richelieu's honour.