1905 – Albert Einstein publishes the article On the Electrodynamics of Moving Bodies, in which he introduces special relativity.
1906 – The United States Congress passes the Meat Inspection Act and Pure Food and Drug Act.
1934 – The Night of the Long Knives, Adolf Hitler's violent purge of his political rivals in Germany, takes place.
1966 – The National Organization for Women, the United States' largest feminist organization, is founded.
