This is a timeline of events that stretched over the period of World War II in 1941, marked also by the beginning of Operation Barbarossa on the Eastern Front.

January 1 January Accounting of the next night's bombing of London reveals that the Old Bailey, the Guildhall, and eight churches by Christopher Wren were destroyed or badly damaged. RAF bombs aircraft factories in Bremen, Germany. 2 January: German bombers bomb Ireland for the second night in a row. 2–4 January: Bardia is bombed by British bombers and bombarded by naval vessels off shore. 3 January: RAF bombers attack Bremen and the Kiel Canal in Germany. The Kiel Canal Bridge suffers a direct hit and collapses on Finnish ship Yrsa. 5 January Operation Compass: Australian troops of XIII Corps (the re-designated Western Desert Force) capture Italian-held Bardia and 45,000 Italian prisoners are taken. Tobruk, the next target, is 70 miles away. The leader of Wallonia's fascist party, Léon Degrelle, gives a speech in the German-occupied city of Liège announcing the support of the Rexist Party for German Nazism.

6 January: The Greeks advance towards Klisura Pass. 7 January: British and Commonwealth offensive in North Africa nears Tobruk; the airport is taken. 10 January Lend-Lease introduced into the U.S. Congress. German–Soviet Border and Commercial Agreement is signed. German aircraft damage aircraft carrier HMS Illustrious, which is heading for Malta. The German Luftwaffe, it is now clear, has command of air over the Mediterranean. The attack is also the opening of Malta's agony over the next months. Greek forces in Albania take the strategically important Klissoura pass. 11 January: In London, 57 people are killed and 69 injured when a German bomb lands outside the Bank of England, demolishing the Underground station below and leaving a 120-foot crater. 12 January: Operation Compass: British and Australian troops of XIII Corps prepare for the assault on Italian-held Tobruk. 13 January: Heavy Luftwaffe night raid on Plymouth. 14 January: First use of "V for Victory" by Victor de Laveleye on the BBC's Belgian service, Radio Belgique. 15 January: The rivalry between Chinese Nationalists and Chinese Communists becomes more evident; large numbers of the latter are forced to give up their arms. 16 January British forces start the first attacks of their East African counter-offensive, on Italian-held Ethiopia, from Kenya. German bombers pound Valletta, Malta, and HMS Illustrious is hit again. 17 January The Battle of Ko Chang ended in a decisive victory for the Vichy French naval forces during the Franco-Thai War. Molotov meets German Ambassador Schulenburg in Moscow. The Soviets are surprised that they have not received any answer from Germany to their offer to join the Axis (November 26, 1940). Schulenburg replies that it has to be first discussed with Italy and Japan. 18 January: Air raids on Malta are increasing in focus and intensity. 19 January The 4th and 5th Indian Divisions continue the British counter-offensive in East Africa, attacking Italian-held Eritrea from the Sudan. Hitler and Mussolini meet at Berchtesgaden; Hitler agrees to provide aid in North Africa. 21 January Operation Compass: British and Australian troops of XIII Corps complete capture of Italian-held Tobruk. There are reports that Romanian Fascist ("Iron Guards") are executing Jews in Bucharest. 23 January HMS Illustrious, heavily damaged, leaves Malta for repairs in Alexandria. Charles Lindbergh testifies before the U.S. Congress and recommends that the United States negotiate a neutrality pact with Adolf Hitler. 24 January: British forces in Kenya continue the East African counter-offensive, attacking Italian Somaliland. 29 January: Death of the Greek dictator, Ioannis Metaxas. 30 January: British forces in North Africa take Derna; 100 miles west of Tobruk. 31 January: Indian 4th Division flanks and then captures Agordat, Eritrea, Italian East Africa. 1,000 Italian troops and 43 field guns are captured.

February 1 February: Admiral Husband Kimmel is appointed the Commander of the US Navy in the Pacific. 3 February Lieutenant-General Erwin Rommel is appointed head of "German Army troops in Africa." This unit is later to be officially designated as the "Afrika Korps". Germany forcibly restores Pierre Laval to office in Vichy. 7 February: Operation Compass: After several days of desperate fighting, a flying column of XIII Corps called Combe Force cuts off the retreating Italian 10th Army during the Battle of Beda Fomm. The Italians are unable to break through the small blocking force and the British accept the surrender of roughly 130,000 Italians in and to the south of Benghazi. 8 February: US House of Representatives passes the Lend-Lease bill. 9 February Mussolini is informed that German reinforcements are on the way to North Africa. British forces reach El Agheila, Cyrenaica. British battleships shell Genoa and British aircraft attack Livorno. Churchill again pleads with the US: "give us the tools." 10 February: Malta's critical period: now through March, it is under heavy daily attack. 11 February Elements of the Afrika Korps start to arrive in Tripoli, Tripolitania. British forces enter Italian Somaliland. 14 February Rommel arrives in Tripoli. Afrika Korps starts to move eastward towards the advance British positions at El Agheila. The British in North Africa have been weakened by the transfer of some troops to Greece. 15 February: Deportation of Austrian Jews to ghettos in Poland begins. 19 February: The start of the "three nights Blitz" of Swansea, South Wales. Over these three nights of intensive bombing, Swansea town centre is almost completely obliterated. 20 February: German and British troops confront each other for the first time in North Africa—at El Agheila in western Libya. 21 February: German forces move through Bulgaria toward the Greek front. 24 February German U-boat offensive in the Atlantic is now increasingly successful. Admiral Darlan is appointed the head of the Vichy government in France. 25 February The British submarine sinks the Italian cruiser Armando Diaz in one of the numerous sea battles in the North African campaign. Mogadishu, the capital of Italian Somaliland, is captured by British forces during the East African Campaign. 28 February: RAF planes bomb Asmara, Eritrea.

March

1 March Hitler gives orders for the expansion of Auschwitz prison camp, to be run by Commandant Rudolf Höss. Bulgaria officially signs the Tripartite Pact. 4 March British commandos carry out an attack on oil facilities at Narvik in Norway. British military force in Libya is thinned down as some men are sent to assist the Greeks in their emerging battle with approaching German troops. Prince Regent Paul of Yugoslavia agrees to join the Axis pact. 7 March: First British troops land in Greece, at Piraeus. 8 March: Another bombing of London, notable because Buckingham Palace is hit. 9 March: The Italian Spring Offensive in the Albanian front begins. 10 March British and Italian troops meet in a brief conflict in Eritrea. Portsmouth suffers heavy casualties after another night of heavy bombing by the Luftwaffe. 11 March: United States President Franklin Delano Roosevelt signs the Lend Lease Act (now passed by the full Congress) allowing Britain, China, and other Allied nations to purchase military equipment and to defer payment until after the war. 12 March: German Panzers arrive in North Africa providing heavy armor for the first major German offensive. 13 March: The Luftwaffe strikes with a large force at Glasgow and the shipping industry along the River Clyde. 17 March Huge convoy losses in mid-Atlantic this week. The United States of America converts its Corps Areas to Defense Commands, with the term Corps reassigned as an intermediate field command of a Field Army. 19 March: The worst bombing of London so far this year, with heavy damage from incendiary bombs; Plymouth and Bristol are bombed again. 20 March: The Italian Spring Offensive is called off, after heavy losses and virtually no progress. 21 March: The Yugoslav cabinet resigns in protest against Prince Paul's pact with the Nazis. Street demonstration occurs, expressive of a deep dislike for Germany. 24 March: Rommel attacks and reoccupies El Agheila, Libya in his first offensive. The British retreat and within three weeks are driven back to Egypt. 25 March: Italian MTMs of the Decima MAS sink the heavy cruiser , a large tanker (the Norwegian Pericles), another tanker and a cargo ship in Suda Bay, Crete. 27 March Crown Prince Peter becomes Peter II of Yugoslavia and takes control of Yugoslavia after an army coup overthrows the pro-German government of the Prince Regent. Japanese spy Takeo Yoshikawa arrives in Honolulu, Hawaii and begins to study the United States fleet at Pearl Harbor. Hitler orders his military leaders to plan for the invasion of Yugoslavia. British forces advancing from the Sudan win the decisive Battle of Keren in Eritrea. Battle of Cape Matapan: the British navy meets an Italian fleet off southern Greece. The battle continues until the 29th. 31 March: The Afrika Korps continues the German offensive in North Africa; Mersa Brega, north of El Agheila, is taken.

April

1 April British retreat after the losses at El Agheila, Libya. Rommel is surprised, then decides to continue his offensive. During this month the heavy bombing of British cities continues, and convoy losses remain heavy. In Iraq, pro-German Rashid Ali and other members of the "Golden Square" stage a military coup d'état and overthrow the regime of the pro-British Regent 'Abd al-Ilah. Rashid Ali names himself Chief of a "National Defence Government". 2 April: After taking Agedabia, Rommel decides to take all of Libya and moves his troops toward Benghazi. All of Cyrenaica (Libya) seems ready for the taking. 3 April A pro-Axis government is installed in Iraq. Bristol, England, suffers another heavy air attack. British troops take Asmara, the capital of Eritrea, from the Italian armies. Rommel takes Benghazi, Libya; Tobruk will remain a threat for the next seven months. Hungarian Prime Minister Pál Teleki commits suicide. 4 April Rommel is now about 200 miles east of El Agheila, heading for Tobruk and Egypt. An Atlantic convoy suffers almost 50% losses to U-boat campaign. 6 April Forces of Germany, Italy, and Hungary, moving through Romania and Hungary, initiate the invasions of Yugoslavia and Greece. The Italian Army is driven out from Addis Ababa, Ethiopia. The northern wing of Rommel's forces take Derna, on the Libyan coast. The southern wing moves toward Mechili, and takes it on the 8th. 7 April: The Luftwaffe begins a two-day assault on Belgrade, Yugoslavia; Hitler is infuriated by the Yugoslav resistance. 8 April: The Germans take Salonika, Greece. 9 April: The Palestinian leader Amin al-Husseini issues a fatwa in a radio speech from Baghdad, calling on Muslims to engage in a holy war against Great Britain. 10 April Greenland is occupied by the United States. With the approval of a "free Denmark", the US will build naval and air bases as counters to the U-boat war. While still being invaded, the Kingdom of Yugoslavia is split up by Germany and Italy. The Independent State of Croatia (Nezavisna Država Hrvatska, NDH) is established under Ante Pavelić and his Ustaša. Germans encircle the port of Tobruk, Libya, opening the siege; some of Rommel's forces move east to take Fort Capuzzo and Sollum, on the border with Egypt. The destroyer attacks a German U-boat that had just sunk a Dutch freighter. The Niblack was picking up survivors of the freighter when it detected the U-boat preparing to attack. The Niblack attacked with depth charges and drove off the U-boat. 11 April Though still a "neutral" nation, the United States begins sea patrols in the North Atlantic. Heavy Luftwaffe raids on Coventry and Birmingham, England.