April 2 Oxford won the 90th Boat Race. It is the first Boat Race to be televised.

April 4 Eleanor Roosevelt, the First Lady of the United States, hosts the White House Conference on Participation of Negro Women and Children in Federal Welfare Programs.

April 6 American chemist Roy J. Plunkett discovers polytetrafluoroethylene, better known as Teflon.

April 9 Hitler speaks in Vienna to a national audience on the eve of the referendum on the Anschluss, making a final appeal to vote in its favour.

April 10 Parliamentary elections are held in Nazi Germany. The Nazi Party claims 99% of the vote.

April 18 Action Comics #1 published by Detective Comics, Inc. premiers on American newsstands bearing a cover date of June 1938.The iconic cover marks the first appearance of Superman, created by Jerry Siegel and Joe Shuster and for that reason is considered the beginning of the superhero genre.

April 20 After holding out for all of spring training and missing Opening Day, Joe DiMaggio accepts a salary offer of $25,000 from the New York Yankees - a $10,000 raise over his 1937 salary. DiMaggio had been holding out for $40,000 but Yankees owner Jacob Ruppert never budged from his first offer.

April 25 The George Orwell book Homage to Catalonia is published.

April 29 Bernard Madoff, businessman convicted of fraud, is born in Queens, New York.

April 30 The animated short film Porky's Hare Hunt is released, marking the first appearance of an unnamed rabbit character that would evolve over the course of later cartoons into Bugs Bunny. (source: Wikipedia)