National Cherry Cheesecake Day
National Picnic Day
Lover’s Day
April 23, 1533 – The Church of England declared that Henry VIII of England and Catherine of Aragon are not married.
Birthday of William Shakespeare (April 23, 1564).
Anniversary of the death of Miguel de Cervantes Saavedra in 1616; Spanish novelist, author of Don Quixote.
Dutch Boats in a Gale
Birthday of Joseph Mallord William Turner (1775), English landscape painter, admired for unusual use of light and color.
See Famous Works of J. M. W. Turner.
1789 – U.S. President George Washington moved into Walter Franklin House (also known as the Samuel Osgood House), New York. It was the first executive mansion.
Birthday of James Buchanan, (1791), 15th president of the United States. Scholars consistently rank Buchanan as one of the two or three worst American presidents because he did not act to prevent the Civil War.
1900 – The word “hillbilly” was first used in print in an article in the “New York Journal.” It was spelled “Hill-Billie”. It was defined as:
“A Hill-Billie is a free and untrammeled white citizen of Alabama, who lives in the hills, has no means to speak of, dresses as he can, talks as he pleases, drinks whiskey when he gets it, and fires off his revolver as the fancy takes him.”
1910 – Theodore Roosevelt made his The Man in the Arena speech.
“It is not the critic who counts; not the man who points out how the strong man stumbles, or where the doer of deeds could have done them better. The credit belongs to the man who is actually in the arena, whose face is marred by dust and sweat and blood; who strives valiantly; who errs, who comes short again and again, because there is no effort without error and shortcoming; but who does actually strive to do the deeds; who knows great enthusiasms, the great devotions; who spends himself in a worthy cause; who at the best knows in the end the triumph of high achievement, and who at the worst, if he fails, at least fails while daring greatly, so that his place shall never be with those cold and timid souls who neither know victory nor defeat.”
Oklahoma Day celebrating the anniversary of the opening of the Oklahoma Territory for settlement in 1889.
1915 – The New York Yankees wore pinstripes and the hat-in-the-ring logo for the first time.
April 22, 1994: Death of 
1910 Death of Samuel Langhorne Clemens (Mark Twain). Upon hearing of Twain’s death, 
The United States Air Force retired the F-117 Nighthawk on April 21, 2008.
U.S. Congress passed an act creating the 
Birthday of Lucretia Garfield (April 19, 1832), wife of 
1861 – Colonel Robert E. Lee turned down an offer to command the Union armies during the U.S. Civil War.
1956 – Actress Grace Kelly and Prince Rainier of Monaco were married. The religious ceremony took place April 19.
Mary Surratt was arrested on April 17, 1865 as a conspirator in Lincoln’s assassination. Sentenced to death, she was hanged on July 7, 1865, becoming the first woman executed by the United States federal government.
Cartoon characters Daffy Duck, Elmer J Fudd & Petunia Pig, debut in 1937.
Ford Mustang was introduced to the North American market in 1964.
Nolan Ryan strikes out his 3,500th batter in 1983. He ranks first all-time in strikeouts at 5,714. He struck out 15 or more players in a game 26 times, second only to Randy Johnson who had 28.
In 1908 the 
April 15, 1452 was the birthday of Leonardo da Vinci, (Leonardo di ser Piero da Vinci), Italian Renaissance polymath: painter, sculptor, architect, musician, mathematician, engineer, inventor, etc. 
1865 – Death of 
1912 – The British passenger liner RMS Titanic hit an iceberg in the North Atlantic at 23:40 (sank morning of April 15th). Titanic had an estimated 2,224 people on board; more than 1500 of them died. In accordance with existing practice, Titanic’s lifeboat system was designed to ferry passengers to nearby rescue vessels, not to hold everyone on board simultaneously.