March 31st

1945: In the Southeast, the Red Army enters German territory near Sopron in Hungary, while capturing Ratibor in Upper Silesia. In the West, the US Third Army reaches Siegen 20 miles east of the Rhine.
source: http://www.feldgrau.com/march.html

1921: Formation of the Royal Australian Air Force - The Australian Air Force became the Royal Australian Air Force (RAAF) on 31 August 1921.
source: http://www.awm.gov.au/atwar/thismonth/mar.htm

1854 - Commodore Matthew Perry negotiates Treaty of Kanagawa to open trade between U.S. and Japan
1971 - Poseidon (C-3) missile becomes operational when USS James Madison began her 3rd patrol carrying 16 tactical Poseidon missiles.
1992 - USS Missouri (BB-63), the last active American battleship is decommissioned.
source: http://www.history.navy.mil/wars/datesmar.htm

1942 - In World War II, Japanese forces invadeChristmas Island, then a British possession.
source: http://en.wikipedia.org/wiki/March_31

1865: Fighting at White Oak Road and Dinwiddie Court House

The final offensive of the Army of the Potomac gathers steam when Union General Phil Sheridan moves against the left flank of Confederate General Robert E. Lee's Army of Northern Virginia. The limited action set the stage for the Battle of Five Forks on April 1.
source: http://www.history.com/this-day-in-history.do?

April 1st

1945: In the East, bitter fighting rages in the western suburbs of the fortress city of Breslau. In the Southeast, the Soviet 3rd Ukrainian Front (Tolbukhin) reaches Wiener Neustadt in its advance toward Vienna. In the West, the US Ninth Army (Simpson) reaches Lippstadt, thus trapping 300,000 German troops of Heeresgruppe B (Model) in the socalled Ruhr pocket.
source: http://www.feldgrau.com/april.html

1921: First AIF disbanded - During the four years of the First World War the first AIF gained a reputation for military prowess remains very much in the consciousness of Australians to the present day.
source: http://www.awm.gov.au/atwar/thismonth/apr.htm

1893 - Navy General Order 409 of 25 February 1893 establishes the rate of Chief Petty Officer as of this date.
1942 - First Naval Air Transportation Service (NATS) squadron for Pacific operations commissioned
1966 - The command, US Naval Forces Vietnam established
1967 - Helicopter squadron HAL 3 activated at Vung Tau
source: http://www.history.navy.mil/wars/datesapr.htm

1572 - in the Eighty Years' War, the Watergeuzen capture Brielle from the Spaniards, gaining the first foothold on land for what would become the Dutch Republic.
1865 - American Civil War: Battle of Five Forks - In Siege of Petersburg, ConfederateGeneralRobert E. Lee begins his final offensive.
1924 - The Royal Canadian Air Force is formed.
1945 - World War II: Operation Iceberg - United States troops land on Okinawa in the last campaign of the war.
source: http://en.wikipedia.org/wiki/April_1

1865 : Richmond captured - The Rebel capital of Richmond falls to the Union, the most significant sign that the Confederacy is nearing its final days.
1918: the Allied Supreme War Council formally confers the post of commander in chief on the Western Front to General Ferdinand Foch.
source: http://www.history.com/tdih.do

1941: General Platt and his 'Northern Force' capture Asmara, the capital of Eritrea. A pro-axis coup, led by Raschid Ali seizes power in Iraq.
1942: Japanese begin landing in Dutch New Guinea. The Japanese force the Chinese out of Toungoo, north of Rangoon.
1945: The U.S. Tenth Army, with 1,457 ships in support, invades Okinawa which is 325 miles from Japan. 60,000 troops land unopposed and establish an 8-mile bridgehead. The 3rd Ukrainian Front capture Sopron in Hungary, a vital road junction between Budapest and Vienna and also reaches Wiener Neustadt as it continues its advance toward Vienna. The fighting in Breslau continues. The U.S. First and Ninth Armies link up at Lippstadt cutting off a third of a million German troops in the Ruhr area. The U.S. First Army enters Hamm, 40 miles Northeast of Essen.
source: http://www.worldwar-2.net/timelines/timelines-index.htm

1941: Peru -Canadian armed merchant cruiser Prince Henry intercepts two German ships off Peru; ships scuttled.
source: http://www1.sympatico.ca/cgi-bin/on_this_day?mth=Apr&day=01

1918: The Royal Air Force was established in Britain.
source: http://www.nytimes.com/learning/general/onthisday/20080401.html

April 2nd

1941: The German Afrikakorps captures Agedabia in Libya.
1942: Axis air forces begin a bombing campaign against La Valetta, the British naval base on Malta in the Mediterranean.
source: http://www.feldgrau.com/april.html

1917: Private J.C. Jensen, VCPrivate J.C. Jensen, 50th Battalion, originally from Loegstoer, Denmark, wins the Victoria Cross at Noreuil, France
source: http://www.awm.gov.au/atwar/thismonth/apr.htm

1781 - Frigate Alliance captures 2 British privateers, Mars and Minerva
1827 - First Naval Hospital construction begun at Portsmouth, VA
1898 - Adoption of U.S. Naval Academy coat of arms
1947 - UN places former Japanese mandated islands under U.S. trusteeship
1951 - First Navy use of jet aircraft as a bomber, launched from a carrier, USS Princeton.
1960 - USS Glacier begins 12 days of relief operations, providing helicopter and boat transportation and emergency supplies to residents of Paramaribo, Suriname after floods.
source: http://www.history.navy.mil/wars/datesapr.htm

1801 - Napoleonic Wars: Battle of Copenhagen - The British destroy the Danish fleet.
1865 - American Civil War: Siege of Petersburg broken - Union troops capture the trenches around Petersburg, Virginia, forcing Confederate General Robert E. Lee to retreat.
1917 - World War I: The Battle of Vimy Ridge commences when the Canada Corps launches an artillery bombardment of the Germantrenches. To that time, the biggest artillery bombardment in history.
1972 - Vietnam War: Easter Offensive begins - North Vietnamese soldiers of the 304th Division take the northern half of Quang Tri Province.
1975 - Vietnam War: Thousands of civilian refugees flee from the Quang Ngai Province in front of advancing North Vietnamese troops.
1982 - Falklands War: 1982 invasion of the Falkland Islands by Argentina. See also 1833 invasion of the Falkland Islands by United Kingdom
source: http://en.wikipedia.org/wiki/April_2

1941: German Lieutenant General Erwin Rommel, "the Desert Fox," resumes his advance into Cyrenaica, modern-day Libya, signaling the beginning of what nine days later will become the recapture of Libya by the Axis forces. Early Italian successes in East Africa, which included occupying parts of Sudan, Kenya, and British Somaliland, were soon reversed after British offensives, led by British Field Marshall Archibald Wavell, resulted in heavy Italian casualties and forced the Italians to retreat into Libya. But Axis control of the area was salvaged by the appearance of Rommel and the Afrika Korps, sent to East Africa by the German High Command to bail their Italian ally out.
source: http://www.history.com/tdih

1940: Hitler gives orders that the invasion of Denmark and Norway is to begin on the 9th April 1940.
1941: The 5th Light Division recaptures Agedabia from the British and fans out into three columns, two of which race across the desert in an attempt to cut off the retreating British, while the third pushes up the coast road towards Benghazi. Rear Admiral Bonnetti, the commander of the Italian Red Sea Flotilla orders his seven destroyers out on 'do or die' missions. All the destroyers are sunk or captured without achieving any worthwhile results.
1942: British retreat from Prome, upper Burma.
1944: The Russians announce their entry into Romania and threaten to shoot one third of all German POWs if the 18 divisions of the trapped 1st Panzer Army do not surrender. The Russian army crosses the river Prut, East of Cernovcy and liberates the little city Gerca.
1945: The 3rd Ukrainian Front and Bulgarian forces take Nagykanizsa, thereby gaining control of the main Hungarian oil production region. 2nd Ukrainian front under Malinovsky conquers the industrial area of Mosonmagyarovar and reaches the Austrian border between Dounau and the Neusiedler lake. The British 7th Armoured Division enters Rhine on Dortmund-Ems canal, 60 miles Northeast of Essen.
source: http://www.worldwar-2.net/timelines/timelines-index.htm

April 3rd

1945: In the East, while the siege of Breslau in Silesia continues, the Red Army captures Bratislava, capital of Slovakia. In the West, units of the British Second Army (Dempsey) reach Münster; the US Ninth Army captures Recklinghausen in the Ruhr, while the US First Army (Hodges) takes Fulda and Kassel.
source: http://www.feldgrau.com/april.html

1885: Tamai was the largest and most significant engagement in which the 770 man New South Wales contingent to the Sudan were involved. In comparison with the British units involved in the battle, Australian involvement was minimal.
source: http://www.awm.gov.au/atwar/thismonth/apr.htm

1797 - CAPT Thomas Truxtun issued first known American signal book using numerary system
1942 - ADM Nimitz named Commander-in-Chief, Pacific Ocean Areas, a joint command, and retained his other title, Commander-in-Chief, Pacific Fleet
1992 - First five coed recruit companies from Orlando, FL Naval Training Center granduate.
source: http://www.history.navy.mil/wars/datesapr.htm

1865 - American Civil War: Union forces capture Richmond, Virginia, the capital of the Confederate States of America.
1982 - Great Britain dispatched a naval task force to the south Atlantic to reclaim the disputed Falkland Islands from Argentina.
source: http://en.wikipedia.org/wiki/April_3

1916: St. Eloi Belgium - Second Canadian Division troops see action at St. Eloi in Flanders; until April 20.
source: http://www1.sympatico.ca/cgi-bin/on_...mth=Apr&day=03

1942: Japanese aircraft bomb Mandalay in central Burma, killing 2,000. They met no opposition from the RAF as all its aircraft had by now been withdrawn to India. The final Japanese offensive on Bataan begins with a five hour artillery and air bombardment, after which the Japanese launch infantry attacks supported by some tanks, which allows them to make penetrations in to US-Filipino defensive positions.
1944: Forty-two Royal Navy, fleet Air Arm Barracuda torpedo-bombers hit the Battleship Tirpitz 14 times in a daring raid on the Alten Fjord, in Norway.
1945: MacArthur is appointed as C-in-C of land forces in the Pacific. Admiral Nimitz is appointed as C-in-C of all naval forces in the Pacific. The Austrian resistance leader Major Szokoll and Russian military authorities confer about co-operation on the Russian offensive against Vienna. The 2nd Ukrainian front advances close to Vienna. The Russians breach the German defensive lines between Wiener Neustadt and Neusiedler lake. Hard fighting continues as the Red Army advances towards Bratislava.
source: http://www.worldwar-2.net/timelines/timelines-index.htm

April 4th

1945: The British Second Army captures Osnabrück, while the US Third Army (Patton) advancing toward Leipzig takes Suhl and Gotha. The US 8th Air Force launches its heaviest raid to date (700 bombers) against Kiel on the Baltic.
source: http://www.feldgrau.com/april.html

1918: First action at Villers-BretonneuxVillers Bretonneux, overlooking the Somme and within artillery range of Amiens, was a principal objective when the Germans renewed their March offensive in early April. They were repulsed by British units of the 5th Australian Division.
source: http://www.awm.gov.au/atwar/thismonth/apr.htm

1776 - Continental Navy frigate Columbus captures HM Tender Hawke, first American capture of British armed vessel
1854 - Sailors and Marines from sailing sloop, Plymouth, protect U.S. citizens at Shanghai
1898 - Appointment of first Civil Engineering Corps officer, Mordecai Endicott, as Chief, Bureau of Yards and Docks
1949 - Establishment of NATO
source: http://www.history.navy.mil/wars/datesapr.htm

1918 - World War I: Second Battle of the Somme ends.
1945 - World War II: American troops liberate Ohrdruf forced labor camp in Germany.
1945 - World War II: Soviet Army takes control of Hungary.
1975 - Vietnam War: Operation Baby Lift - A United States Air ForceC-5A Galaxy crashes near Saigon, South Vietnam shortly after takeoff, transporting orphans - 172 die.
2007 - 15 British Royal Navy personnel held in Iran are released by the Iranian President.
source: http://en.wikipedia.org/wiki/April_4

1949: CANADA JOINS NATO - Canada signs the North Atlantic Treaty with Belgium, Britain, Denmark, France, Iceland, Italy, Luxembourg, the Netherlands, Norway, Portugal and the U.S.; becomes founding member of North Atlantic Treaty Organization; NATO members pledge to defend each other in event of Soviet attack.
1942: Sri Lanka - RCAF Squadron Leader L.J. Birchall spots Japanese fleet heading for Ceylon; alerts naval base and averts disaster for the British Fleet and a second Pearl Harbour.
source: http://www1.sympatico.ca/cgi-bin/on_this_day?mth=Apr&day=04

1776: After the successful siege of Boston, General George Washington begins marching his unpaid soldiers from their headquarters in Cambridge, Massachusetts, toward New York in anticipation of a British invasion.
source: http://www.history.com/tdih.do

1941: German and Italian troops enter Benghazi unopposed.
1944: The 17th Indian Division reaches the Imphal plain after a 20-day fighting retreat. Japanese forces begin five weeks of attacks to reach Imphal from the South and begin their attack on Kohima, Assam. Army Group Centre, under General Busch launches a counterattack which succeeds in reaching German units surrounded at Kovel in the Pripet swamps since the 19th March.
1945: The Russian 2nd and 3rd Ukrainian front complete the liberation of Hungary. Troops of the 2nd Ukrainian front capture Bratislava. The Germans forces counterattack in Moravska-Ostrava and Nitra. The US Third Army advancing toward Leipzig takes Suhl and Gotha and finally clears Kassel of German resistance. The British Second Army captures Osnabrück. The French First Army enters Karlsruhe.
source: http://www.worldwar-2.net/timelines/timelines-index.htm

9th. of april 1940 at 0400 in the morning, after being passed by heavy German Navy forces in the Oslofjord, the commander of Rauøy Fortress recieves a telephonecall that German troops has landed on the other side of the bay and are making inquiries about the location of the fortress.

At 0530 in the morning, battery commander of the northern 15 cm. battery, captain H.E. Sørlie discover 4 boats landing troops on a beach just 900 meters (1000 yards) from the battery.
4 machinegun crews are sendt out with the order to try and pin the enemy down and deny them access to the rest of the island.
Taking advantage of the time bought by the machineguns, the crew on the #2 cannon manages to clear away all the camoflague and other obstacles between the gun and the beach, they hack off the electrical wires blocking the path and hand-crank the 15 cm cannon in the right direction.
The breech is opened and captain Sørlie takes a rough aim through the barrell, the enemy is in cover behind a rock, and captain Sørlie decides to start shooting at it.
After some 45 shells is fired they recieve orders to surrender the fortress.

Two Norwegians fell in that fight, while the combined effort of the machineguns and the #2 cannon of the northern battery made sure that around 200 of the 300 Germans landing on the bach that morning would never see daylight again.

Bitteress spread among the crew on the fortress when it turned out that the order to surrender was a mistake and meant for another fort.

One day late, but I just had to post it anyway..

In an act of irony, the German heavy cruiser Blücher was sunk in the Oslofjord April 9 1940 by 48-year-old German Krupp guns (named Moses and Aron, of 28 cm calibre, installed at Oscarsborg Fortress in May 1893) and equally ancient torpedoes:

* German ships sailed up the fjord leading to Oslo, reaching the Drøbak Narrows (Drøbaksundet). In the early morning of April 9, the gunners at Oscarsborg Fortress fired on the leading ship, the Blücher, which had been illuminated by spotlights at about 0515hrs. Within two hours, the ship, unable to maneuver in the narrow fjord, was sunk with about 600-1,000 men. The now obvious threat from the fortress delayed the rest of the naval invasion group long enough for the Royal family and Parliament to be evacuated, along with the national treasury. As a result, Norway never surrendered to the Germans, leaving the Quisling government illegitimate and permitting Norway to participate as an Ally in the war, rather than as a conquered nation.

http://en.wikipedia.org/wiki/Operation_Weser%C3%BCbung

Originally Posted by Redleg

One day late, but I just had to post it anyway..

In an act of irony, the German heavy cruiser Blücher was sunk in the Oslofjord April 9 1940 by 48-year-old German Krupp guns (named Moses and Aron, of 28 cm calibre, installed at Oscarsborg Fortress in May 1893) and equally ancient torpedoes:

One might add that the commander of Oscarsborg personally disregarded the ROE that called for warning shots fired with blanks, and ordered all the pieces to be loaded with live shells, and aimed for direct fire.
Due to a desperate lack of personell there was at least 2 cooks hauling grenades from the storage that morning, the entire kitchen staff were ordered to act as cannoneers, and the commander himself pre-aimed the guns.
He later explained that he didn't believe he had time to reload and fire another salvo under the present circumstances.

Also the commanding officer on the torpedobattery was called into duty some few days before, ha was actually retired at the time and was far older than the main battery on the fortress...

April 5th

1942: Hitler orders plans for the execution of Fall Blau (Operation Blue), the new summer offensive on the southern front in the East designed to reach the Volga, as well as to capture the Caucasus oilfields.
1944: German forces of Heeresgruppe Mitte (von Kluge) encircled in the Kowel pocket are relieved after bitter fighting.
1945: The Soviet 3rd Ukrainian Front reaches the outskirts of Vienna which has minimal German forces to defend it. In the West, the French First Army (de Tassigny) captures Karlsruhe on the upper Rine. The US 8th Air Force carries out another heavy attack (450 bombers) against Kiel which causes severe damage to the cruisers Hipper and Emden.
source: http://www.feldgrau.com/april.html

1951: 3rd Battalion, Royal Australian Regiment, involved in Operation Rugged, Korea - Operation Rugged involved United Nations' forces crossing the 38th Parallel and occupying strong defensive positions formed by a line of hills codenamed the Kansas Line and including Hills Salmon, Cod and Sardine, 45 kilometres north of Seoul.
source: http://www.awm.gov.au/atwar/thismonth/index.asp

1885: Winnipeg Manitoba - Two permanent artillery batteries arrive in Winnipeg.
source: http://www1.sympatico.ca/cgi-bin/on_this_day?mth=Apr&day=05

1242 - During a battle on the ice of Chudskoye Lake, Russian forces rebuff an invasion attempt by the Teutonic Knights.
1654 - The Treaty of Westminster, ending the First Anglo-Dutch War, is signed.
1862 - American Civil War: Battle of Yorktown. The battle begins when Union forces under GeneralGeorge McClellan close in on the ConfederatecapitalRichmond, Virginia. (Editor's note: The first battle for Yorktown during the Revolutionary War was the one for which two World War II aircraft carriers were named for.)
1942 - Second World War: Japanese Navy attacks Colombo in Ceylon (Sri Lanka). Royal NavyCruisersHMS Cornwall and HMS Dorsetshire are sunk southwest of the island.
1972 - Vietnam War: North Vietnamese forces invade Binh Long Province, launching a second front of the Nguyen Hue Offensive.
source: http://en.wikipedia.org/wiki/April_5

1982: A British Naval Task Force leaves for the Falkland Islands, which have been invaded by Argentina
source: http://www.tnl.net/when/4/5

1946 - USS Missouri arrives in Turkey to return the body of Turkish ambassador to the U.S. and to show U.S. support and willingness to defend Turkey.
source: http://www.history.navy.mil/wars/datesapr.htm

1918: First stage of German spring offensive ends - General Erich von Ludendorff formally ends “Operation Michael,” the first stage of the final major German offensive of World War I. Operation Michael had produced the biggest gains of territory on the Western Front by either side since 1914. The Germans had advanced almost 40 miles, inflicted some 200,000 casualties and captured 70,000 prisoners and more than 1,000 Allied guns. The costs of battle were high, however: Germans suffered nearly as many casualties as their enemies and lacked the fresh reserves and supplies the Allies enjoyed following the American entrance into the war.
source: http://www.historychannel.com/tdih/

1917: German forces finish their withdrawal to the Hindenburg Line.
1940: RAF launch attacks against ships at Wilhelmshaven. Norway and Sweden are both informed of the allied intention to mine Norwegian waters.
1942: Fuhrer Directive 41 rolls off the mimeograph machines in Rastenberg and the Wehrmacht has its marching orders for 1942. Leningrad is to finally be captured, but that's a secondary objective. The big plan is in the South, which involves 2nd Army and 4th Panzer Army breaking through to Voronezh on the Don. 6th Army will break out South of Kharkov and combine with the 4th Panzer Army to surround the enemy. After that, the 4th Panzer Army and 6th Army will drive East under the command of Army Group B and surround Stalingrad from the North, while Army Group A's 17th Army and 1st Panzer Army will do so from the South. Once Stalingrad is taken, the 6th Army will hold the flank defense line while Army Group A drives South into the Caucasus to seize the oilfields and become the northern punch of a grand pincer movement (the southern half being Rommel) to seize Suez, the Nile Delta, the Middle-East and its oilfields.
1944: The RAF and USAAF conduct the first of 24 round-the-clock raids on the Ploiesti oil refineries in Romania. A Jewish inmate, Siegfried Lederer, escapes from Auschwitz-Birkenau and makes it safely to Czechoslovakia. He then warns the Elders of the Council at Theresienstadt about Auschwitz.
1945: A U.S. military government is established on Okinawa. The US 8th Air Force carries out another heavy attack (450 bombers) against Kiel. The 3rd Ukrainian Front reaches the railway North West of Vienna, cutting rail link with Linz. Eighteen U.S. divisions begin the clearance of Ruhr Pocket.
source: http://www.worldwar-2.net/timelines/timelines-index.htm

1964: Army Gen. Douglas MacArthur died at age 84.
source: http://www.nytimes.com/learning/general/onthisday/20080405.html

April 6th

1941: German, Italian and Hungarian forces begin the invasion of Yugoslavia and Greece. The Luftwaffe carries out several devastating bombing raids against Belgrade.
1942: Axis bombers attack the port of Alexandria in Egypt.
1943: Units of Heeresgruppe A (von Weichs) begin an offensive against the Black Sea port of Novorossisk in the Caucasus. US and British forces in Tunisia launch an attack against 5.Panzerarmee (von Arnim).
1945: In the East, after eliminating the Heiligenbeil pocket, the Soviet 3rd Belorussian Front (Vassilevsky) reaches the Baltic coast in East Prussia, separating communications between 2.Armee (von Tippelkirch) defending besieged Königsberg and 4. Armee (Hossbach) holding the Vistula delta N of Marienbrg. In the Southeast, Tito partisans occupy Sarajevo in Bosnia.
source: http://www.feldgrau.com/april.html

1942: US 41st Division arrives in Australia - Between December 1941 and August 1945 some one million Americans were stationed in Australia.
1952: 1st Battalion, Royal Australian Regiment, arrives in Korea The Battalion remained in Korea until September 1953.source: http://www.awm.gov.au/atwar/thismonth/apr.htm

1862 - American Civil War: Battle of Shiloh begins - In Tennessee, forces under UnionGeneralUlysses S. Grant meet Confederate troops led by GeneralAlbert Sidney Johnston at Shiloh.
1865 - American Civil War: Battle of Sayler's Creek - ConfederateGeneralRobert E. Lee's Army of Northern Virginia fights its last major battle while in retreat from Richmond, Virginia.
1917 - World War I: United States declares war on Germany
1941 - World War II: Operation Castigo begins; Germany invades Kingdom of Yugoslavia and Greece.
source: http://en.wikipedia.org/wiki/April_6

1942: Aldershott England -General Andrew G.L. (Andy) McNaughton 1887-1966 forms the First Canadian Army in Britain with five divisions, two armored brigades, and 3 other divisions slated for home defence.
source: http://www1.sympatico.ca/cgi-bin/on_this_day?mth=Apr&day=06

1776 - Sloop-of-war Ranger, frigate Queen of France and frigate Warren capture British Hibernia and 7 other vessels
1862 - Naval Gunfire from Tyler and Lexington help save Union Troops at Battle of Shiloh
1909 - Commander Robert E. Peary reports reaching the North Pole
1917 - U.S. declares war on Germany
1945 - First heavy kamikaze attack on ships at Okinawa.
1961 - USS Lake Champlain brings oxygen to aid stricken passenger of British liner Queen of Bermuda.
1968 - USS New Jersey recommissioned for shore bombardment duty in Vietnam
source: http://www.history.navy.mil/wars/datesapr.htm