| 1870s | Tribal warfare decimates the local population. German traders on Nauru request protection from the Imperial Government. |
| 1886 | | Anglo-German Convention signed recognizing German sovereignty over Nauru. |
| 1888 | April 14 | Nauru annexed to the German colony of the Marshall Islands. |
| 1898 | | First resident German administrator arrives on Nauru. Alcohol is banned and firearms and ammunition confiscated from the natives. |
| 1899 | | First Christian missionaries arrive on Nauru. Development of Nauruan orthography and translation of the Bible into Nauruan begins. |
| 1900 | | Albert Ellis an employee of J.T. Arundel Ltd. of London examines a chunk of wood being used for a doorstop in his office in Sydney. The specimen, brought back as a souvenir of a visit to Nauru, turns out to be high quality phosphate. |
| 1906 | April 1 | Nauru is annexed to German New Guinea along with the other Marshall Islands. |
| 1907 | | The British owned Pacific Phosphate Company begins mining operations on Nauru. |
| | Translation of the Bible into Nauruan completed. |
| 1914 | November | Nauru is occupied without resistance by the Australian Navy. |
| 1919 | | An influenza epidemic kills one third of Nauru’s population. June 28 |
| | Treaty of Versailles signed. Germany renounces sovereignty over Nauru. |
| July 2 | The British, Australian and New Zealand Governments purchase the assets of the Pacific Phosphate Company for £3,500,000. A three member board of British Phosphate Commissioners (one from each country) is appointed to oversee mining operations on Nauru. |
| 1920 | December 17 | The League of Nations ratifies a joint Australian, British and New Zealand mandate over Nauru (administered by Australia). |
| 1940 | December 6 | The British Phosphate Commission ship Triona, bound for Nauru, is intercepted by a German raider north of the Solomon Islands. The passengers and crew are held captive while the Germans loot the ship before scuttling it. |
| December 7 – 8 | German raiders Orion, Komet and Kulrnerland disguised as Japanese merchant ships sink four phosphate freighters off Nauru. |
| December 27 | German raider Komet shells British Phosphate Commission facilities and the wireless station on Nauru. |
| 1941 | December 8 | Japanese aircraft bomb Nauru’s wireless station. |
| 1942 | February 23 | Le Triomphant, a Free French destroyer, arrives from the New Hebrides and evacuates 61 Europeans, 391 Chinese and 49 members of Nauru’s military garrison. |
| August 26 | A 300 man Japanese taskforce lands on Nauru. The remaining 191 Europeans are made prisoner. The 1,850 Nauruans are allowed the freedom of the island but place on food rations. |
| 1943 | January | A Japanese airfield built by 1,500 Korean laborers and 300 Nauruan and Gilbertese conscripts becomes operational. |
| March 25 | American bombers destroy 15 Japanese aircraft and damage airfield facilities on Nauru. The Japanese execute 5 British prisoners in retaliation. Afterward, 1,200 Nauruans are deported to Truk in the Caroline Islands to alleviate food shortages on the island. |
| 1945 | September 13 | Japanese forces on Nauru surrender to HMAS Dimantina. |
| 1946 | January | The 737 surviving Nauruan deportees are repatriated from Truk. |
