April 30

311 – The Diocletianic Persecution of Christians in the Roman Empire ends. 1315 – Enguerrand de Marigny is hanged at the instigation of Charles, Count of Valois. 1492 – Spain gives Christopher Columbus his commission of exploration. He is named admiral of the ocean sea, viceroy and governor of any territory he discovers. 1513 – Edmund de la Pole, Yorkist pretender to the English throne, is executed on the orders of Henry VIII. 1557 – Mapuche leader Lautaro is killed by Spanish forces at the Battle of Mataquito in Chile. 1598 – Juan de Oñate begins the conquest of Santa Fe de Nuevo México. 1598 – Henry IV of France issues the Edict of Nantes, allowing freedom of religion to the Huguenots. 1636 – Eighty Years' War: Dutch Republic forces recapture a strategically important fort from Spain after a nine-month siege. 1789 – On the balcony of Federal Hall on Wall Street in New York City, George Washington takes the oath of office to become the first President of the United States. 1803 – Louisiana Purchase: The United States purchases the Louisiana Territory from France for $15 million, more than doubling the size of the young nation. 1812 – The Territory of Orleans becomes the 18th U.S. state under the name Louisiana. 1838 – Nicaragua declares independence from the Central American Federation. 1863 – A 65-man French Foreign Legion infantry patrol fights a force of nearly 2,000 Mexican soldiers to nearly the last man in Hacienda Camarón, Mexico. 1871 – The Camp Grant massacre takes place in Arizona Territory. 1885 – Governor of New York David B. Hill signs legislation creating the Niagara Reservation, New York's first state park, ensuring that Niagara Falls will not be devoted solely to industrial and commercial use. 1897 – J. J. Thomson of the Cavendish Laboratory announces his discovery of the electron as a subatomic particle, over 1,800 times smaller than a proton (in the atomic nucleus), at a lecture at the Royal Institution in London. 1900 – Hawaii becomes a territory of the United States, with Sanford B. Dole as governor.