19 Feb 1941 The Australian 8th Division arrived in Singapore.
28 Apr 1941 Winston Churchill, without reference to the Chiefs of Staff, issued a directive stating that there is no need at the present time to make provisions for the defence of Malaya and Singapore.
13 Nov 1941 Allied troops established a new defensive line from the mouth of the Muar River to Gemas in British Malaya.
25 Nov 1941 Japanese troops transports en route to Malaya were detected off Taiwan.
2 Dec 1941 US PBY Catalina patrol aircraft reported 20 Japanese transports congregating in Cam Ranh Bay off Indochina.
3 Dec 1941 US PBY Catalina patrol aircraft reported 30 Japanese transports congregating in Cam Ranh Bay off Indochina, 10 more than the previous day. Meanwhile, a Japanese fleet departed Hainan Island in southern China for Thailand.
4 Dec 1941 Japanese invasion fleets departed from various locations for their destinations in Malaya and Thailand. Later this day, American PBY Catalina patrol aircraft reported that the 30 Japanese transports detected on the previous day in Cam Ranh Bay off Indochina were no longer there.
5 Dec 1941 Japanese invasion fleet boarded a Norwegian freighter and destroyed her radio.
6 Dec 1941 US Navy yacht Isabel was detected by a floatplane from Japanese seaplane carrier Kamikawa Maru off Indochina; Isabel was later ordered to abort her current mission as bait for first fire and to sail for Manila, Philippine Islands. Shortly after, nearby, a Japanese Zero fighter covering the Malaya invasion force found and shot down a British PBY Catalina patrol aircraft.
7 Dec 1941 Japanese troops invaded Khota Baru, Malaya, two hours before the attack on Pearl Harbor, US Territory of Hawaii. A series of landings in nearby Thailand initially met stiff resistance, but the Thai government negotiated for an armistice within hours.
8 Dec 1941 RAF Hudson aircraft bombed Japanese invasion shipping off Kota Bharu, British Malaya, setting cargo ship Awajisan Maru afire. The Japanese 143rd Infantry Regiment of 55th Division (under command of 25th Army) landed on four beaches in southern Thailand; local Thai forces, unaware of their government's agreement to allow free passage to the Burma border, put up a fierce resistance and killed 79 Japanese soldiers. Japanese aircraft began arriving at Songkla in southern Thailand to prepare for air raids against targets in British Malaya.
9 Dec 1941 Bitter fighting between British and Japanese troops took place for the airfield at Kota Bharu in British Malaya, while two groups of Indian troops crossed into Thailand to destroy roads and railroads. In Thailand, the Japanese entered Bangkok. Out at sea, Japanese aircraft and submarine I-65 spotted British battleship HMS Prince of Wales and battlecruiser HMS Repulse; torpedo bombers were launched from Saigon, occupied French Indochina, but they failed to locate the ships.
10 Dec 1941 Japanese submarine I-58 spotted British battleship HMS Prince of Wales and battlecruiser HMS Repulse off British Malaya, launched five torpedoes, but all of them missed; beginning at 1117 hours, Japanese aircraft began to attack. Overwhelmed, HMS Repulse was sunk at 1233 hours (513 killed), followed by HMS Prince of Wales at 1318 hours (327 killed); destroyers HMS Electra, HMS Express, and HMS Vampire rescued 1,862 survivors. On land, the British commanders dispatched the 1st Battalion of the 14th Punjab Regiment and the 2nd Battalion of the 1st Gurkha Rifles regiment to Changlun and Asun in northern British Malaya to counter the Japanese advance; contact was made at Changlun at 2100 hours, where two Japanese tanks were destroyed before the Punjabi troops fell back toward Asun.
11 Dec 1941 Japanese infantrymen under the command of Colonel Shizuo Saeki overran the defenses set up by Punjabi troops between Changlun and Asun, British Malaya, and gave chase into Asun, where Gurkha troops slowed the Japanese advance by destroying the two Japanese tanks in the spearhead; the Gurkha positions, however, would be captured by 1900 hours, killing or capturing 350 men. Nearby, Japanese troops also under Saeki reached the outskirts of Jitra, British Malaya, which was defended by troops of the 11th Indian Division. Out at sea, Japanese pilot Lieutenant Ito, flying a torpedo bomber over the location where Repulse and Prince of Wales were sunk on the previous day, dropped a wreath to honor the killed British sailors.
12 Dec 1941 Colonel Shizuo Saeki led elements of the Japanese 5th Division attacked Jitra, British Malaya. After sundown, British General Lewis Heath gave the order for the 11th Indian Division to withdraw from Jitra.
13 Dec 1941 Just after 0000 hours, Dutch submarine O.16 entered Mueang Patani, Thailand and damaged four Japanese freighters with six torpedoes, sinking a number of them in shallow water. All ships would later be repaired and put back into service. At 0200 hours, rearguard Indian troops blew up the bridge at Jitra, British Malaya before joining the main body falling back toward Gurun to the south. Later on the same day, Japanese troops arrived at the abandoned airfield at Alor Setar, British Malaya, capturing bombs and aviation fuel.
14 Dec 1941 At 1500 hours, Japanese troops overran Allied defenses near Gurun, British Malaya but failed to reach the town.
15 Dec 1941 Japanese troops overran the Allied defenses at Gurun, British Malaya, opening up the road toward Penang. On the same day, the British abandoned the RAF base at Butterworth near Penang, flying all of of the remaining aircraft to Singapore.
16 Dec 1941 European civilians began to evacuate from Penang, Malaya while Allied troops destroyed guns, ammunition dumps, and other military facilities to prevent Japanese capture; the radio station and the ships in the harbor, however, were overlooked and would later be pressed into Japanese service.
17 Dec 1941 British and Indian troops established a defensive line 65 miles south of Penang, British Malaya near the Perak River.
19 Dec 1941 Japanese troops captured Penang, Malaya.
20 Dec 1941 Two RAF Buffalo fighters attacked the Japanese barracks at Victoria Point, Burma near the border with Thailand, inflicting heavy casualties. Meanwhile, in Malaya, Japanese troops attempted to flank the Allied positions on the Perak River while another column marched along the Grik Road.
21 Dec 1941 Having seen previous success with the same tactic on a smaller scale, Japanese launched a large number of rafts down the Perak River toward Kuala Kangsar, Malaya in an attempt to bypass nearby roadblocks; casualties were heavy, but the Japanese troops were able to establish a bridgehead downstream, causing the British to abandon the Perak River positions and to fall back.
25 Dec 1941 The Allies completed the abandonment of defensive positions along the Perak River in Malaya and established new positions at Ipoh about 10 miles to the south.
26 Dec 1941 Anglo-Indian and Japanese troops clashed at Chemor, Malaya north of Ipoh. Later in the day, the Allies withdrew from Ipoh and fell back to Kampar 25 miles to the south.
27 Dec 1941 Japanese bombers attacked Kuala Lumpur, British Malaya. Meanwhile, Japanese troops advanced toward Kampar in western Malaya and Kuantan on the east coast.
28 Dec 1941 Indian 22nd Brigade arrived at Kuantan, Malaya.
30 Dec 1941 8,000 troops of the 9th Brigade of the Japanese 5th Division launched probing attacks on Kampar on the west coast of British Malaya. On the east coast, Japanese troops attacked the defensive positions north of the Kuantan River, whose defenders were confused by inaccurate intelligence that the Japanese were to land from the sea behind them.
31 Dec 1941 British 155th Field Regiment of the Lanarkshire Yeomanry stopped a Japanese attack at Kampar, British Malaya; further south on the western coast, the Japanese landed behind the Allied lines. On the east coast, the Indian 9th Division fell back to the south side of the Kuantan River. Far to the south, at Singapore, British and Dutch transports took on civilians for evacuation to South Africa. Finally, off the Chinese coast, 56 Japanese troop transports departed the island of Taiwan, escorted by 3 cruisers and 16 destroyers, for an amphibious operations in British Malaya.
1 Jan 1942 Japanese troops continued the assault on Kampar, British Malaya; both sides incurred heavy casualties in the morning. Meanwhile, Japanese 11th Regiment landed in the Bernam River 35 miles to the southwest. In London, England, United Kingdom, Winston Churchill complained of the British Royal Navy's inability to disrupt Japanese shipping in Malayan waters.
2 Jan 1942 Japanese and Anglo-Indian troops continued to fight at Kampar Hill in British Malaya and prepared to withdraw southward later in the day. To the south, troops of the Japanese 4th Imperial Guard Regiment sailed down the Perak River to reinforce the Japanese 11th Regiment at Bernam River; Indian 12th Infantry Brigade arrived to reinforce the failing defense at Telok Anson nearby. Far to the south, Japanese aircraft based in Malaya and Borneo attacked Singapore.
3 Jan 1942 The Japanese made an amphibious attack at Kuala Selangor in western Malaya, which was repelled by Indian troops. In eastern Malaya, Japanese troops pushed through Indian 9th Division defenses and crossed the Kuantan River, capturing the airfield nearby.
4 Jan 1942 Indian 11th Infantry Division withdrew from Kampar Hill in western Malaya, falling back to a new defensive line at the Slim River.
5 Jan 1942 Japanese troops launched probing attacks at the defenses manned by Indian troops at Trolak, British Malaya; 60 Japanese were killed without achieving success.
7 Jan 1942 Japanese tanks wiped out the Indian 11th Division at Slim River, British Malaya early in the morning; by 0930 hours, both the road and railway bridges were secured by Japanese troops.
8 Jan 1942 Japanese troops penetrated the outer lines of defense at Kuala Lumpur, Malaya,