Sir Alexander Cadogan succeeds Sir Robert Vansittart as permanent under-secretary at the British Foreign Office; Vansittart is "kicked upstairs" by being given the new office of Chief Diplomatic Advisor to the Government.
Sir Nevile Henderson, British Ambassador to Germany, presents a proposal to Hitler for an international consortium to rule much of Africa (in which Germany would be assigned a leading role) in exchange for a German promise never to resort to war to change her frontiers; Hitler rejects the British offer.
March 12 – Anschluss: German troops occupy Austria; annexation is declared the following day.
March 14 – French Premier Léon Blum reassures the Czechoslovak government that France will honor its treaty obligations to aid Czechoslovakia in event of German invasion.
April 16 – London and Rome sign an agreement that sees Britain recognise Italian control of Ethiopia in return for an Italian pledge to withdraw all its troops from Spain at the conclusion of the civil war there.
April 18 – First appearance of Superman (as an untested[clarification needed] lead feature), in Action Comics #1 (cover date June). The date is established in court documents released during the legal battle over the rights to Superman. On April 18, 2018, DC Comics released Action Comics #1000.
General Ludwig Beck, Chief of the German Army's General Staff, submits a memorandum to Hitler opposing Fall Grün (Case Green), the plan for a war with Czechoslovakia, under the grounds that Germany is ill-prepared for the world war likely to result from such an attack.
May 12 – U.S. Secretary of State Cordell Hull rejects the Soviet Union's offer of a joint defence pact to counter the rise of Nazi Germany.
May 23 – No evidence of German troop movements against Czechoslovakia is found and May Crisis subsides. Germany is, nevertheless, perceived to have backed down in the face of Czechoslovak mobilization and international diplomatic unity but the issue of the future of the Sudetenland is far from resolved.
July 22 – Britain rejected a proposal from its ambassador in Berlin, Nevile Henderson, for a four power summit on Czechoslovakia consisting of Britain, France, Germany and the U.S.S.R. London would under no circumstances accept the U.S.S.R. as a diplomatic partner.
August 31 – Winston Churchill, still believing France and Britain mean to honor their promises to defend Czechoslovakia against Nazi aggression, suggests in a personal note to Neville Chamberlain that His Majesty's Government may want to set up a broad international alliance including the United States (specifically mentioning U.S. President Franklin D. Roosevelt as possibly receptive to the idea) and the Soviet Union.
September – The European crisis over German demands for annexation of the Sudeten borderland of Czechoslovakia becomes increasingly severe.
September 4 – During the ceremony marking the unveiling of a plaque at Pointe de Grave, France, celebrating Franco-American friendship; American Ambassador William Bullitt in a speech states, "France and the United States were united in war and peace", leading to much speculation in the press that if war did break out over Czechoslovakia, then the United States would join the war on the Allied side.
September 6 – What eventually proves to be the last of the "Nuremberg Rallies" begins. It draws worldwide attention because it is widely assumed Hitler, in his closing remarks, will signal whether there will be peace with or war over Czechoslovakia.
September 9 – U.S. President Franklin D. Roosevelt disallows the popular interpretation of Bullitt's speech at a press conference at the White House. Roosevelt states it is "100% wrong" the U.S. would join a "stop-Hitler bloc" under any circumstances and makes it quite clear that in the event of German aggression against Czechoslovakia, the U.S. would remain neutral.
September 12 – Hitler makes his much-anticipated closing address at Nuremberg, in which he vehemently attacks the Czech people and President Beneš. American news commentator Hans von Kaltenborn begins his famous marathon of broadcast bulletins over the CBS Radio Network with a summation of Hitler's address.
September 13 – The followers of Konrad Henlein begin an armed revolt against the Czechoslovak government in Sudetenland. Martial law is declared and after much bloodshed on both sides order is temporarily restored. Neville Chamberlain personally sends a telegram to Hitler urgently requesting that they both meet.
September 17 – Neville Chamberlain returns temporarily to London to confer with his cabinet. The U.S.S.R. Red Army masses along the Ukrainian frontier. Rumania agrees to allow Soviet soldiers free passage across her territory to defend Czechoslovakia.
During a meeting between Neville Chamberlain, the recently elected Premier of France, Édouard Daladier, and Daladier's Foreign Minister, Georges Bonnet, it becomes apparent neither the British nor the French governments are prepared to go to war over the Sudetenland. The Soviet Union declares it will come to the defence of Czechoslovakia only if France honours her commitment to defend Czechoslovak independence.
Mussolini makes a speech in Trieste, Italy where he indicates that Italy is supporting Germany in the Sudeten crisis.
In the early hours of the day, representatives of the French and British governments call on Czechoslovak President Edvard Beneš to tell him France and Britain will not fight Hitler if he decides to annex the Sudetenland by force. Late in the afternoon the Czechoslovak government capitulates to the French and British demands.
Unable to survive the previous day's capitulation to the demands of the English and French governments, Czechoslovak premier Milan Hodža resigns. General Jan Syrový takes his place.
Neville Chamberlain arrives in the city of Bad Godesberg for another round of talks with Hitler over the Sudetenland crisis. Hitler raises his demands to include occupation of all German Sudeten territories by October 1. That night after a telephone conference, Chamberlain reverses himself and advises the Czechoslovaks to mobilize.
As the Polish army masses along the Czech border, the Soviet Union warns Poland that if it crosses the Czech frontier, Russia will regard the 1932 non-aggression pact between the two countries as void.
Sir Eric Phipps, British Ambassador to France, reports to London, "all that is best in France is against war, almost at any price", being opposed only by a "small, but noisy and corrupt, war group". Phipps's report creates major doubts about the ability and/or willingness of France to go to war.
At 1:30 AM, Adolf Hitler and Neville Chamberlain conclude their talks on the Sudetenland. Chamberlain agrees to take Hitler's demands, codified in the Godesberg Memorandum, personally to the Czech Government. The Czech Government rejects the demands, as does Chamberlain's own cabinet. The French Government also initially rejects the terms and orders a partial mobilization of the French army.
September 26 – In a vitriolic speech at Berlin's Sportpalast, Hitler defies the world and implies war with Czechoslovakia will begin at any time.
September 28 – As his self-imposed October 1 deadline for occupation of the Sudetenland approaches, Adolf Hitler invites Italian Duce Benito Mussolini, French Premier Edourd Deladier and British Prime Minister Neville Chamberlain to one last conference in Munich. The Czechs themselves are not invited.
Munich Agreement: German, Italian, British and French leaders agree to German demands regarding annexation of the Sudetenland in Czechoslovakia. The Czechoslovak government is largely excluded from the negotiations and is not a signatory to the agreement.
October 1 – German troops march into the Sudetenland. The Polish government gives the Czech government an ultimatum stating that Zaolzie region must be handed over within twenty-four hours. The Czechs have little choice but to comply. Polish forces occupy Zaolzie.
October 18 – The German government expels 12,000 Polish Jews living in Germany; the Polish government accepts 4,000 and refuses admittance to the remaining 8,000, who are forced to live in the no-man's land on the German-Polish frontier.
November 9 – Holocaust – Kristallnacht: In Germany, the "night of broken glass" begins as Nazi activists and sympathizers loot and burn Jewish businesses (the all night affair sees 7,500 Jewish businesses destroyed, 267 synagogues burned, 91 Jews killed and at least 25,000 Jewish men arrested).
November 12 – French Finance Minister Paul Reynaud brings into effect a series of laws aiming at improving French productivity (thus aiming to undo the economic weaknesses which led to Munich), and undoes most of the economic and social laws of the Popular Front.
The Czechoslovak parliament elects Emil Hácha as the new president of Czechoslovakia.
Benito Mussolini and his Foreign Minister Count Galeazzo Ciano order "spontaneous" demonstrations in the Italian Chamber of Deputies, demanding that France cede Tunisia, Nice, Corsica and French Somaliland to Italy. This begins an acute crisis in Franco-Italian relations that lasts until March 1939.
December – President Roosevelt agrees to loan $25 million to Chiang Kai-shek, cementing the Sino-American relationship and angering the Japanese government.
December 1 – Slovakia granted the status of an autonomous state under the Catholic priest Fr. Joseph Tiso.
December 6 – German Foreign Minister Joachim von Ribbentrop visits Paris, where he is allegedly informed by French Foreign Minister Georges Bonnet that France now recognizes all of Eastern Europe as being in Germany's exclusive sphere of influence. Bonnet's alleged statement (he subsequently always denies making the remark) to Ribbentrop is a major factor in German policy in 1939.