May 1: Batman, created by Bob Kane (and, unofficially, Bill Finger) makes his first appearance in a comic book.

May 2: Major League Baseball's Lou Gehrig, the legendary Yankee first baseman known as "The Iron Horse", ends his 2,130 consecutive games played streak after contracting amyotrophic lateral sclerosis. The record stands for 56 years before Cal Ripken, Jr. plays 2,131 consecutive games.

May 3: Vyacheslav Molotov succeeds Maxim Litvinov as Soviet Foreign Commissar. - The All India Forward Bloc is formed by Netaji Subhas Chandra Bose.

May 6: Carl Friedrich Goerdeler tells the British government that the German and Soviet governments are secretly beginning a rapprochement with the aim of dividing Eastern Europe between them. Goerdeler also informs the British of German economic problems which he states threaten the survival of the Nazi regime, and advises that if a firm stand is made for Poland, then Hitler will be deterred from war.

May 9: Spain leaves the League of Nations.

May 14: Lina Medina, a 5-year old Peruvian girl, gives birth to a baby boy, becoming the youngest confirmed mother in medical history.

May 17: King George VI and Queen Elizabeth arrive in Quebec City to begin the first-ever tour of Canada by Canada's monarch. - The British government issues the White Paper of 1939, sharply restricting Jewish immigration to the Palestine Mandate. - Sweden, Norway, and Finland refuse Germany's offer of non-aggression pacts.

May 20: Pan-American Airways begins trans-Atlantic mail service with the inaugural flight of its Yankee Clipper from Port Washington, New York.

May 22: Germany and Italy sign the Pact of Steel.

May 29: Albanian fascist leader Tefik Mborja is appointed as member of the Italian Chamber of Fasces and Corporations. (source: Wikipedia)