April Fools' Day pranks were popularized. (c. 1700) Though no one is sure of the exact year that April Fools' Day got its start, the tradition of April fooling became popular in England sometime in the early 1700s. It's speculated that the whole thing got started when nations changed from the Julian to Gregorian calendars, with those who forgot or didn't hear about the change being the "fools."
A bill that banned cigarette advertising on radio and TV was signed by President Richard Nixon. (1970) Though Nixon was an avid pipe smoker himself, he signed the bill at the insistence of public health advocates. Though studies had come out as early as 1939 detailing the effects that smoking had on health, it was only in the late 1960s that issue really came to the front of popular consciousness.
Hitler was sent to jail. (1924) Hitler was sentenced for an attempted coup known as the Beer Hall Putsch, but the trial brought him a lot of good publicity. He spent nine months in jail, during which time he wrote Mein Kampf, and came out more powerful that ever.
The BBC hosted a spoof documentary on spaghetti trees. (1957) The documentary, which detailed the family based traditions of Swiss spaghetti harvesting, got mixed reviews. Though many were incensed at a news agency reporting fake news, others were simply curious about where to get their own spaghetti trees.
Cincinnati, Ohio, became the first US city to pay its firefighters a regular salary. (1853) The city was the first to have an established fire department, and others followed suit — though early firefighting wasn't always about helping people. Many gang-like wars developed over territory and responsibilities of firefighting crews, most notably in New York.
The internal combustion engine was patented. (1826) Though other versions of the engine had existed before, the first modern internal combustion engine was patented by Samuel Morey on this day. The machine was received lukewarmly, but became popular after his death when another inventor, Charles Edgar Duryea, made the first gas engine.
Apple, Inc. was founded. (1976) The first Apple computers were constructed by hand by one of the founders. The models were sold for $666.66 — over $2,500 US Dollars (USD) in 2010 dollars.
The Netherlands legalized same-sex marriage. (2001) Although same-sex marriages were recognized and performed in different regions before this, the Netherlands was the first country to allow it as a nation. As of 2010, same-sex marriages were still only allowed in 10 other countries besides the Netherlands.
Britain's Royal Air Force (RAF) was established. (1918) Only seven years after the Wright brothers invented the airplane, the RAF was formed. By November 1918, they had over 20,000 planes and about 300,000 pilots and crew.
President Reagan made the first major speech about AIDS. (1987) The subject of AIDS was still largely taboo, and had only been officially recognized as a disease in 1981. Reagan made a speech declaring AIDS "public health enemy number one" on this day.