Frederick Royden Chalmers Frederick Royden Chalmers CMG , DSO ( 4 January 1881 – 25 March 1943 ) was an Australian farmer , soldier , businessman , and government administrator . His murder by Japanese soldiers on Nauru in 1943 was the focus of a war crimes trial following World War II . Biography . Frederick Chalmers , son of Robert Hamilton Chalmers and Emily Lousia ( Walter ) Chalmers , was born in Brighton , Tasmania on 4 January 1881 , into a farming family . He had four brothers and four sisters . At age 18 he enlisted in the army and served in South Africa during the Boer War , obtaining the rank of Lieutenant in 1901 . After demobilization he returned to Tasmania , where he lived until 1907 . He then joined the railway company of the State of Victoria , and worked as a salesman at Moe . Married to Mary Cecilia Bennett in 1910 , he became a widower in 1914 , and in April of the same year he re - enlisted in the Army . Joining the Australian Imperial Force as an enlisted man , he was promoted to lieutenant a month later . During the First World War he served in Egypt , Gallipoli , Belgium , and France . He was promoted to captain in August 1915 . After officers ' training at the military school of Aldershot in England late in 1916 he was promoted to Major . He commanded a battalion in October 1917 , became a lieutenant colonel in January 1918 , and was named Companion of the Order of St . Michael and St . George in 1919 . Returning to Tasmania with his new wife , Lenna Annette French , whom he had married in London in 1917 , he worked for several years in agriculture in Bagdad and in mining on the west coast of Tasmania . He headed an association of veterans and was involved in the Boy Scouts . In 1938 , Chalmers was selected from among 70 candidates to succeed R . C . Garsia as head of the administration of Nauru , a Pacific island supervised by Australia under League of Nations mandate . It had over 3 , 500 inhabitants , and was of strategic importance to the Commonwealth owing to its very large deposits of phosphate ( which was used in fertilizer , making it critical to Australia and New Zealand ' s agriculture - based economies ) . His affable manner made him a popular figure on Nauru . He introduced Berkshire pigs to the island to improve the local livestock , and also fish of the genus " gambusia " to combat the proliferation of mosquitoes . On 27 December 1940 , after the outbreak of the Second World War , an auxiliary cruiser of the Kriegsmarine , the " Komet " , appeared off Nauru ' s shore . After warning the residents via signals , the German commerce raider began shelling the island ' s mining facilities , fuel storage tanks , and cantilevered loading jetties , causing tremendous damage . An infuriated Chalmers reportedly stomped along the waterfront hurling insults at the enemy ship . A year later , after Japan entered the war , the decision was made to evacuate the island . While most Westerners and foreign workers were taken off in February 1942 , Chalmers ( along with four other Australians ) chose to remain behind , feeling it was his duty to look after the Nauruans if the Japanese invaded . When Japanese occupation forces duly landed the following August , Chalmers and the other Australians were interned and kept in a house near the island ' s native hospital . On 25 March 1943 , after an American bombing raid on Nauru ' s Japanese - built airfield , the garrison ' s second - in - command , Lt . Hiromi Nakayama , ordered the execution of the five Australians . Chalmers and his companions were beheaded , bayoneted , or shot ( later testimony varied ) and buried on the beach . After the war Nakayama was found guilty of murder by an Australian war crimes tribunal at Rabaul . He was hanged in August 1946 . A monument to Chalmers , as well as the other victims of the war , was erected on Nauru in 1951 . His wife Lenna died while he was in captivity . They had four daughters ; he had a son and a daughter with his first wife .