| 1937 | |
| 7 July | The Marco Polo Bridge or Lugouqiao Incident. Using the pretext of a missing soldier, the IJA attacks the Chinese Army and total war on China begins. |
| 25–31 July | Fall of Beijing and Tianjin. |
| 9 October | Fall of Shanghai. |
| 1938 | |
| 31 January | Fall of Nanjing (the infamous Nanjing Massacre). |
| 21 October | Fall of Guangzhou. |
| 1939 | |
| 13, 15, 16 February | Japanese planes deliberately attack border posts as well as British military facilities, causing damage and civilian casualties. Flight of Japanese warplanes over Hong Kong is increasingly common. |
| 1940 | |
| June | The Imperial Japanese Navy (IJN) intensifies operations around Hong Kong, harassing fishermen and merchant vessels. The Japanese occupy two of the colony’s islands as well as a British lighthouse, imposing a virtual blockade around Hong Kong. |
| 1941 | |
| 27 October | The Canadian force leaves Vancouver aboard SS Awatea and HMCS Prince Robert for Hong Kong. |
| 6 November | IJA HQ orders the China Southern Expeditionary Army Group to prepare to attack Hong Kong, with the specific order to begin the operation after landings in Malaysia. |
| 16 November | Canadian reinforcements arrive in Hong Kong. |
| 1 December | IJA is notified of the decision to declare war on the United States, the British Empire and the Netherlands. |
| 4 December | Admiral Sir Tom Philips, C-in-C of Britain’s Eastern Fleet, flies back to Singapore from Manila after conferring with MacArthur and Admiral Tom Hart, US Navy, for assistance should Japan attack. Philips comes home empty handed. |
| 7 December | Japanese attack on Pearl Harbor, as well as Guam and Wake Island. All garrison troops are at action stations by the evening. |
| 8 December | 0445hrs Hong Kong time, intelligence sources report hearing Tokyo give coded instructions to Japanese nationals that war with Great Britain and the USA has begun. |
| By 0645hrs local time, the Hong Kong Garrison has been informed that the British Empire and Japan are at war. Japanese attack on Hong Kong begins roughly, nine hours before the attack begins on Pearl Harbor. | |
| 9 December | Attack on the Shing Mun Redoubt late evening. Redoubt falls at 0100hrs, 10 December. |
| 10 December | HMS Prince of Wales and Repulse are sunk. |
| 12 December | Kowloon Peninsula is evacuated. |
| 18 December | The IJA succeeds in landing and securing a foothold on Hong Kong Island. |
| 19 December | The IJA pushes towards Wongneichong Gap by nightfall and reaches the garden of Repulse Bay Hotel; the 2nd MTB flotilla carries out a suicidal raid on IJA landing boats. WO2 Osborne Winnipeg Grenadiers is killed; posthumously awarded the VC. |
| 25 December | Ceasefire is declared at 1515hrs, and surrender document is formally signed at 1800hrs. That same evening one-legged Chinese Navy Rear-Admiral Chan Chak is given command of the remaining Royal Navy boats, together with 60 survivors, and makes a daring escape by sea and on foot to Huizhou (Waichow) China. |
| 1942 | |
| January | The CCP-led (Chinese Communist Party) Guangdong People’s Anti-Japanese East River Guerrilla Column (ERC) is established. The guerrillas conduct conventional guerrilla warfare on land and sea, killing traitors and collaborators, rescuing VIPs, gathering intelligence and rescuing downed American pilots. |
| 23 July | British Army Aid Group (BAAG), a China-based MI9 military intelligence unit, is founded by ex-POW Lt. Col. Lindsey Ride HKVDC (the Hong Kong Volunteer Defence Corps) with the aim of providing aid to escaped Hong Kong POWs and downed Allied airmen, and gathering intelligence. |
| 1 October | Systematic transportation of POWs to Japan for hard labour. More than 800 die after the SS Lisbon Maru, a Japanese transport ship from Hong Kong, is sunk off the coast of eastern China by a US submarine, the USS Grouper. |
| 1943–45 | |
| USAF 14th Air Force’s B-25 and, B-24 bombers, escorted by P-40, P-51 and P-38 fighters, begin regular bombing of Hong Kong and of Japanese shipping around Hong Kong waters. | |
| 1945 | |
| 15 August | Japan surrenders. |
| 30 August | Rear-Admiral Cecil Harcourt, Royal Navy, commanding the 11th Aircraft Carrier Squadron, enters Hong Kong waters. |
| 16 September | Rear-Admiral Harcourt takes formal surrender of Japanese forces under Vice-Adm. Fujita and Lt. Gen. Tanaka in the Governor’s House, Hong Kong. |