FWIW, Google chose to commemorate the 155th anniversary of the Pony Express instead.
Bing did cherry blossoms, and they're usually pretty good about observing history. Still, Lincoln did die on the 15th so we'll see what they do tomorrow.
155th anniversary of the Pony Express
“April is the cruelest month”.
A wide array of “events” occurred in April.
The Titanic sunk, FDR died, MLK assassinated, American Civil war began and ended, the US entered WW1, Bay of Pigs, Battle of Lexington & Concord, Clinton & Reno burn 82 to death at Waco, Hitler dies, Chernobyl, the Mutiny on the Bounty etc., etc., etc...