In History, Today on April 18

El Salvador's Legislative Assembly extends the state of emergency by 30 days amidst a crackdown on gangs following a surge in violence.

NASA's Mars Helicopter Ingenuity performs its first flight on Mars, marking the first powered, controlled flight on another planet.

The redacted version of the Mueller Report was released to the public, detailing the investigation into Russian interference in the 2016 U.S. presidential election.

The South Korean ferry MV Sewol sank, resulting in the deaths of 304 passengers, mostly high school students.

A fertilizer plant exploded in West, Texas, killing 15 people and injuring over 160 others.

A series of bombings in Baghdad, Iraq, killed nearly 200 people, marking one of the deadliest days in the city since the 2003 invasion.

The Vatican and the United States Conference of Catholic Bishops announced new policies to address the sexual abuse scandal within the Catholic Church.

Over 100 countries gather in The Hague for the first UN Conference on Human Settlements (Habitat I), focusing on addressing issues related to human settlements and urbanization.

A suicide bombing attack on the United States Embassy in Beirut kills 63 people, marking the beginning of a series of attacks against U.S. targets in the region during the Lebanese Civil War.

The Republic of Zimbabwe is officially established, marking the end of British colonial rule and the beginning of independence for the nation formerly known as Rhodesia.

Albert Einstein, the renowned theoretical physicist known for developing the theory of relativity, passed away in Princeton, New Jersey.

Gamal Abdel Nasser seizes power in Egypt, beginning a new era of military leadership in the country. His leadership marked the end of British military presence and the start of widespread reforms in Egypt.

The Republic of Ireland Act 1948 came into effect, officially declaring Ireland a republic and severing its last ties with the British Commonwealth.

The Doolittle Raid took place, where 16 American B-25 bombers launched from the USS Hornet to conduct an air raid on Tokyo and other locations on Honshu during World War II, marking the first air operation to strike the Japanese archipelago.

Yankee Stadium, often referred to as 'The House that Ruth Built', opened in the Bronx, New York City.

The 1906 San Francisco earthquake struck the coast of Northern California, causing widespread destruction and resulting in the deaths of an estimated 3,000 people.

The Paris World Exhibition (Exposition Universelle) was opened to the public.

Billy the Kid escapes from the Lincoln County Jail in Lincoln, New Mexico.

The first 'saloon' patent for the ice cream soda was granted.

American forces led by General Winfield Scott captured the Mexican town of Cerro Gordo during the Mexican-American War, after overcoming significant defenses.

The University of Alabama was founded, becoming the state's first public college and one of the oldest public universities in the United States.

Paul Revere and William Dawes embarked on their midnight ride to warn the colonial militia of the approaching British forces before the battles of Lexington and Concord, which marked the beginning of the American Revolutionary War.

William III and Mary II were formally declared King and Queen of England, Scotland, and Ireland; this event is part of the Glorious Revolution, which caused significant constitutional changes, limiting the powers of the monarchy and expanding those of Parliament.

The cornerstone of St. Peter's Basilica was laid in Vatican City, marking the beginning of the construction of one of the most renowned works of Renaissance architecture.

The University of Rome was established by Pope Boniface VIII.

Bolesław I the Brave is crowned in Gniezno Cathedral, becoming the first King of Poland.

The death of Æthelred I, King of Northumbria, occurred on this date. Æthelred I was a king of Northumbria, a kingdom in what is now northern England and southeastern Scotland. His reign was marked by internal strife and external threats, particularly from the Vikings.