- February 2 - World War II: President Franklin D. Roosevelt and British Prime Minister Winston Churchill leave to meet with Soviet leader Joseph Stalin at the Yalta Conference.
- February 3 - World War II: Russia agrees to enter the Pacific Theatre conflict against Japan.
- February 4 - World War II: President Franklin D. Roosevelt, Prime Minister of the United Kingdom Winston Churchill and Soviet leader Joseph Stalin begin the Yalta Conference (ends February 11)
- February 7 - World War II: General Douglas MacArthur returns to Manila
- February 8 - World War II: United States fire bombs Dresden, Germany killing 35,000 citizens.
- February 9 - Walter Ulbricht becomes the leader of German communists in Moscow
- February 10 - World War II: The Steuben sunk by the Soviet submarine S-13.
- February 13 - World War II: Soviet Union forces capture Budapest, Hungary from the Nazis.
- February 13 - World War II: The British Air Force bombs Dresden, Germany.
- February 14 - Chile, Ecuador, Paraguay and Peru join the United Nations.
- February 16 - World War II: American forces land on Corregidor island in the Philippines.
- February 16 - American forces recapture the Bataan Peninsula
- February 19 - World War II: Battle of Iwo Jima - about 30,000 United States Marines landed on Iwo Jima starting the battle.
- February 23 - World War II: Following the American victory at the Battle of Iwo Jima, a group of United States Marines reach the top of Mount Surabachi on the island and are photographed raising the American flag. The photo will later win a Pulitzer Prize.
- February 23 - World War II: The capital of the Philippines, Manila, is liberated by American forces.
- February 24 - Egyptian Premier Ahmed Maher Pasha is killed in Parliament after reading a decree.
- March 1 - Jesse Holman Jones starts his term of office as U.S. Secretary of Commerce, serving under President Franklin D. Roosevelt
- March 3 - World War II: Previously neutral Finland declares war on the Axis powers.
- March 6 - Communist-led government formed in Romania
- March 7 - World War II: American troops seize the bridge over the Rhine River at Remagen, Germany and begin to cross.
- March 8 - Josip Broz Tito forms a government in Yugoslavia
- March 9 – March 10 - World War II: American B-29 bombers attack Japan with incendiary bombs. Tokyo is fire-bombed killing 100,000 citizens.
- March 16 - World War II: The Battle of Iwo Jima ends but small pockets of Japanese resistance persist.
- March 18 - World War II: 1,250 American bombers attack Berlin.
- March 19 - World War II: Adolf Hitler orders that all industries, military installations, shops, transportation facilities and communications facilities in Germany be destroyed.
- March 19 - Off the coast of Japan, bombers hit the aircraft carrier USS Franklin, killing 800 of her crew and crippling the ship.
- March 21 - World War II: British troops liberate Mandalay, Burma
- March 22 - The Arab League was formed with the adoption of a charter in Cairo, Egypt.
- March 30 - World War II: Soviet Union forces invade Austria and take Vienna.
- May 1 - Joseph Goebbels and his wife commit suicide after killing their 6 children. Karl Dönitz appoints Count Lutz Schwerin von Krosigk as the new Chancellor of Germany.
- May 2 - World War II: The Soviet Union announces the fall of Berlin. Soviet soldiers hoist the red flag over the Reichstag building.
- May 2 - World War II: Troops of Yugoslav 4th Army together with Slovene 9th Corpus NOV liberate Trieste.
- May 3 - World War II: Sinking of the floating-jails Cap Arcona, Thielbek and Deutschland by the RAF in the Lübeck Bay.
- May 3 - Rocket scientist Wernher von Braun and 120 members of his team surrender to US forces. They later help start the US space program.
- May 4 - World War II: Liberation of the concentration camp Neuengamme near Hamburg by the British army.
- May 4 - World War II: Reddition of the North Germany army by Marshal Bernard Montgomery.
- May 5 - Ezra Pound, poet and author, is arrested by American soldiers in Italy for treason.
- May 5 - World War II: US armored unit liberates prisoners of Mauthausen concentration camp - including Simon Wiesenthal
- May 5 - World War II: Canadian soldiers liberate the city of Amsterdam from Nazi occupation.
- May 6 - World War II: Axis Sally delivers her last propaganda broadcast to Allied troops (first was on December 11, 1941).
- May 7 - World War II: General Alfred Jodl signs unconditional surrender terms at Reims, France, ending Germany's participation in the war. The document will take effect the next day.
- May 8 - World War II: V-E Day (Victory in Europe, as Nazi Germany surrenders) commemorates the end of World War II in Europe.
- May 8 - World War II: British 8th Army together with Slovene partisan troops and motorized detachment of Yugoslav 4th Army arrives to Carinthia and Klagenfurt.
- May 8-29 - In Algeria, French troops and released Italian POWs defeat rebellion of Algerians
- May 9 - World War II: Hermann Göring is captured by the United States Army; Norway arrests Vidkun Quisling; Soviet Union marks V-E Day.
- May 9 - World War II: General Alexander Löhr Commander of German Army Group E near Topolšica, Slovenia, signs capitulation of German occupation troops.
- May 15 - the last battle of WWII at Poljana near Slovenj Gradec, Slovenia
- May 23 - President of Germany Karl Dönitz and Chancellor of Germany Count Lutz Schwerin von Krosigk are arrested by British forces at Flensburg. They would respectively be the last German Head of state and Head of government until 1949.
- May 23 - Heinrich Himmler, the head of the Nazi Gestapo, commits suicide in British custody.
- May 25 - In Atlantic, ships can finally keep their lights lit. Szilard begs Harry S. Truman not to use the bomb.  (http://www.nuclearfiles.org/hitimeline/1945.html)
- May 28 - William Joyce, known as "Lord Haw-Haw" is captured. He is later charged with high treason in London for his English-language wartime broadcasts on German radio. He is hanged in January of 1946.
- May 29 - Group of German communists, Ulbricht in the lead, arrive in Berlin
- May 30 - Iranian government demands that Soviet and British troops leave the country
- July 1 - World War II: Germany is divided between Allied occupation forces
- July 5 - World War II: Liberation of the Philippines declared.
- July 8 - World War II: Harry S. Truman informed that Japan will talk peace if she can keep the Emperor.  (http://www.nuclearfiles.org/hitimeline/1945.html)
- July 9 - A forest fire breaks out in the Tillamook Burn, the third fire in that area since 1933.
- July 16 - Nuclear testing: The Trinity Test, the first test of an atomic bomb, using 6 kilograms of plutonium, succeeds in detonating, unleashing an explosion equivalent to that of 20 kilotons of TNT.
- July 17 - World War II: Potsdam Conference - At Potsdam, the three main Allied leaders begin their final summit of the war. The meeting will end on August 2.
- July 21 - World War II: Harry S. Truman approves order for atomic bombs to be used.  (http://www.nuclearfiles.org/hitimeline/1945.html)
- July 23 - World War II: French marshall Philippe Pétain, who headed the Vichy government during World War II goes on trial, charged with treason.
- July 26 - Winston Churchill resigns as Britain's prime minister after his Conservative Party is soundly defeated by the Labour Party. Clement Attlee becomes the new prime minister. Potsdam Declaration demands Japan's unconditional surrender; Article 12 permitting Japan to retain the Emperor had been deleted by Truman.  (http://www.nuclearfiles.org/hitimeline/1945.html)
- July 28 - An Army Air Force B-25 bomber accidentally crashes into the Empire State Building, killing 14 people.
- July 28 - World War II: Japan rejects Potsdam Declaration  (http://www.nuclearfiles.org/hitimeline/1945.html).
- July 29 - The BBC Light Programme radio station was launched, aimed at mainstream light entertainment and music.
- July 30 - World War II: The USS Indianapolis is hit and sunk by an I-58 Japanese submarine. Some 900 survivors jump into the sea and are adrift for 4 days. Nearly 600 die before help arrives. Captain Charles Butler MacVey III is later court-martialed.
- July 31 - World War II: Pierre Laval, fugitive former leader of Vichy France, surrenders to Allied soldiers in Austria.
- August 6 - World War II: The United States detonates an atomic bomb nicknamed "Little Boy" on Hiroshima, Japan at 8:16 AM (local time) killing about 10,000 citizens immediately, 60,000 from injuries and sickness before the end of 1945, and 140,000 total from a mixture of radition sickness, injuries, and instant death from the bomb.
- August 8 - The United Nations Charter is ratified by the United States, and that nation becomes the first to join the new international organization. Soviets declare war on Japan.
- August 9 - World War II: The United States detonates an atomic bomb nicknamed "Fat Man" over the city of Nagasaki, Japan at 11:02 AM (local time) with an equivalent force of 22,000 tons of TNT. An estimated 80,000 are killed and more than 60,000 are injured. The bomb was originally meant for the nearby city of Kokura, but bad weather impared the bomber's visual contact with the city. After several failed tries they diverted to their back-up target, Nagasaki. World War II: The Soviet Union begins its offensive against Japan in the then Japanese controlled Chinese region of Manchuria.  (http://www.globalsecurity.org/military/library/report/1986/RMF.htm)
- August 10 - World War II: US drops warning leaflets on Nagasaki.  (http://www.nuclearfiles.org/hitimeline/1945.html)
- August 13 - Zionist World Congress approaches British government to talk about founding of Israel.
- August 15 - World War II: Imperial Japan surrenders, but retains the Emperor. The United States called this day V-J Day (Victory in Japan). This ends the period of Japanese expansionism and begins the period of Occupied Japan.
- August 15 - Korea divided to North and South Korea
- August 17 - Indonesian nationalists Sukarno and Mohammed Hatta declare the independence of Republic of Indonesia, Sukarno as a president. Dutch colonial authorities do not approve
- August 19 - Vietnam War: Viet Minh led by Ho Chi Minh take power in Hanoi, Vietnam.
- End of August - Chinese Civil War: Mao Zedong and Chiang Kai-shek meet in Chongqing to discuss an end to hostilities between the Communists and the Nationalists.
Year in topic
Science and Technology
- Arthur C. Clarke puts forward idea of a communications satellite in a Wireless World magazine article
- At Mayo Clinic, streptomycin first used to treat tuberculosis
- Percy Spencer accidentally discovers that microwaves can heat food. Invention of microwave oven follows.
- Grand Rapids, Michigan, and Newburgh, New York become the first cities to add fluoride to drinking water
- The first nuclear reactor outside of the U.S. is built in Chalk River, Ontario, Canada.
- High-altitude west-to-east winds across Pacific, discovered by Japanese in 1942 and by Americans in 1944, are dubbed "jet stream"
- Salvador Edward Luria and Alfred Day Hershey independently recognize that viruses undergo mutations
- Herbicide 2,4-D is introduced. Later used as a component of Agent Orange
- Team led by Charles DuBois Coryell discovers element 61, the only one still missing between 1 and 96 on Periodic Table. New element is called promethium
- January 3 - Stephen Stills (Crosby, Stills, Nash and Young), singer, songwriter
- January 3 - Victoria Principal, actress
- January 10 - Rod Stewart, singer
- January 19 - Maria Jespen, theologian
- January 26 - Jacqueline du Pré, cello player (d. 1987)
- January 27 - Nick Mason, musician of Pink Floyd
- January 28 - Marthe Keller, actress
- January 29 - Tom Selleck, actor (Magnum, P.I.)
- January 30 - Michael Dorris, author (d. 1997)
- February 3 - Bob Griese, Football Hall of Famer
- February 5 - Charlotte Rampling, actress
- February 6 - Bob Marley, Jamaican roots rock reggae singer and musician (d. 1981)
- February 7 - Pete Postlethwaite, actor
- February 9 - Mia Farrow, actress
- February 14 - Prince Hans-Adam II of Liechtenstein
- February 17 - Brenda Fricker, actress
- February 24 - Barry Bostwick, actor
- February 28 - Bubba Smith, Football Hall of Famer
- March 1 - Dirk Benedict, movie and television actor, perhaps best known for playing the character of "Face" in the television series The A-Team
- March 7 - John Heard, actor
- March 8 - Jim Chapman, American politician
- March 8 - Micky Dolenz, actor, director, musician ("The Monkees")
- March 8 - Anselm Kiefer, painter
- March 19 - Cem Karaca, Turkish rock musician
- March 22 - Paul Schockemöhle, equestrian
- March 29 - Walt Frazier, basketball player
- March 30 - Eric Clapton, blues guitarist
- April 2 - Linda Hunt, actress
- April 4 - Daniel Cohn-Bendit, political activist
- April 4 - Craig T. Nelson, actor (Coach, The District)
- April 9 - Peter Gammons, baseball sportswriter, journalist
- April 27 - August Wilson, playwright
- May 4 - Narasinham Ram, journalist
- May 6 - Bob Seger, rock music singer
- May 6 - Jimmie Dale Gilmore, musician
- May 8 - Keith Jarrett, jazz musician
- May 13 - Magic Dick, musician ("The J. Geils Band")
- May 15 - Duarte Pio, Duke of Braganza presumptive heir to Portuguese crown
- May 19 - Pete Townshend, guitarist, lyricist
- May 21 - Ernst Messerschmid, physicist and astronaut
- May 28 - John Fogerty, singer
- May 31 - Rainer Werner Fassbinder, director
- June 15- Her Royal Highness Princess Michael of Kent
- June 17 - Art Bell - radio talk show host
- June 17 - Eddy Merckx, Belgian cycling champion
- June 17 - Anupam Kher, actor, India
- June 19 - Aung San Suu Kyi, Myanmar poet, politician and Nobel peace laureate
- June 25 - Carly Simon, singer, songwriter
- July 7 - Michael Ancram (Michael Kerr, Earl of Ancram), British politician
- July 8 - Micheline Calmy-Rey, member of the Swiss Federal Council
- July 9 - Dean R. Koontz, fiction author
- July 15 - Jürgen Möllemann, German politician (d. 2003)
- July 24 - Azim Premji, Indian businessman
- July 28 - Jim Davis, cartoonist
- August 9 - Posy Simmonds, cartoonist
- August 14 - Steve Martin, actor and comedian
- August 15 - Mahamandaleshwar Paramhans Swami Maheshwarananda, Hindu Guru
- August 31 - Itzhak Perlman, violinist
- August 31 - Van Morrison, musician
- September 3 - Aldo Moro, Italian politician
- September 8 - Jose Feliciano, singer
- October 12 - Aurore Clément, French actress
- October 15 - Jim Palmer, Baseball Hall of Famer
- October 25 - David Schramm, astrophysicist
- October 27 - Luís Inácio Lula da Silva, Brazilian President
- October 30 - Henry Winkler, actor (Happy Days)
- November 3 - J. D. Souther, country rock musician
- November 5 - Jacques Lanctôt, FLQ terrorist
- November 12 - Neil Young, (Crosby, Stills, Nash and Young), singer, songwriter
- November 15 - Anni-Frid Lyngstad, Norwegian singer
- November 26 - Daniel Davis, actor (The Nanny)
- January 3 - Edgar Cayce, psychic, "exhaustion"
- January 22 - Else Lasker-Schuler, poet
- January 31 - Eddie Slovik, American soldier
- February 5 - Lilian Rolfe, SOE agent executed by the Nazis
- February 5 - Violette Szabo, SOE agent executed by the Nazis
- February 5 - Denise Bloch, SOE agent executed by the Nazis
- February 11 - Al Dubin, Swiss songwriter
- February 11 - J. S. H. Lokerman, Dutch resistance fighter
- February 17 - Gabrielle Weidner, Belgian heroine of World War II
- February 21 - Eric Liddell, Scottish runner
- March - Anne Frank, at Bergen-Belsen concentration camp, typhus
- March 1 - Umenosuke Bessho, Japanese writer (b. 1871)
- March 2 - Emily Carr, artist
- March 18 - William Grover-Williams, Grand Prix motor racing driver/war hero
- March 19 - Friedrich Fromm, Nazi official
- March 23 - Elisabeth de Rothschild, executed by the Nazis
- March 26 - David Lloyd George, Prime Minister of the United Kingdom
- March 30 - Elise Rivet, Roman Catholic nun and war hero
- April 9 - Wilhelm Canaris, head of the German Abwehr, hanged for treason
- April 9 - Dietrich Bonhoeffer, theologian in Nazi Germany
- April 12 - United States President Franklin Delano Roosevelt, massive stroke
- April 18 - Ernie Pyle, American journalist, sniper fire
- April 28 - Benito Mussolini, Italian dictator, hanged
- April 30 - Adolf Hitler, German dictator and Nazi party leader, suicide
- May 1 - Cecily Lefort SOE agent, WW II heroine, executed by the Nazis
- May 1 - Joseph Goebbels, Nazi propagandist, suicide
- May 15 - Charles Williams, British author
- May 23 - Heinrich Himmler, head of the Nazi Gestapo, suicide
- June 15 - Nikola Avramov, painter (b. 1897)
- July 5 - John Curtin, fourteenth Prime Minister of Australia
- August 2 - Pietro Mascagni, Italian composer
- August 9 - Harry Hillman, American athlete
- August 10 - Robert Goddard, American rocket scientist
- August 31 - Stefan Banach, Polish mathematician
- September 15 - Anton Webern, Austrian composer
- September 24 - Johannes Hans Geiger, inventor of the Geiger counter
- September 26 - Béla Bartók, aged 64, Hungarian composer
- October 13 - Milton Hershey, chocolate tycoon
- October 15 - Pierre Laval, former Vichy French premier, firing squad
- October 19 - N.C. Wyeth, illustrator
- October 24 - Vidkun Quisling, Norwegian politician, famous traitor, executed
- November 11 - Jerome Kern, composer
- November 21 - Robert Benchley, The New Yorker, humorist, theatre critic, actor
- December 4 - Thomas Hunt Morgan, biologist
- December 20 - General George S. Patton, car accident
- December 28 - Theodore Dreiser, author