April 18

Events

796day.year

King Æthelred I of Northumbria is murdered in Corbridge by a group led by his ealdormen, Ealdred and Wada. The patrician Osbald is crowned, but abdicates within 27 days.

King Æthelred I of Northumbria was murdered in Corbridge by his own nobles, leading to the brief reign and abdication of Osbald.
On April 18, 796, King Æthelred I of Northumbria was assassinated in Corbridge. A group of powerful ealdormen, led by Ealdred and Wada, conspired against him. Æthelred's murder reflected deep unrest among the Northumbrian nobility. Following his death, the patrician Osbald was hastily crowned as king. His rule was unstable and lasted just 27 days before he abdicated. These events highlight the volatile nature of early medieval Northumbrian politics. They also set the stage for further power struggles in the region.
796 Æthelred I of Northumbria Corbridge ealdormen Osbald
1428day.year

Peace of Ferrara between Republic of Venice, Duchy of Milan, Republic of Florence and House of Gonzaga: ending of the second campaign of the Wars in Lombardy fought until the Treaty of Lodi in 1454, which will then guarantee the conditions for the development of the Italian Renaissance.

The 1428 Peace of Ferrara ended the second campaign of the Wars in Lombardy, paving the way for the later Treaty of Lodi.
Signed on April 18, 1428, the Peace of Ferrara brought an end to hostilities among the Republic of Venice, the Duchy of Milan, the Republic of Florence, and the House of Gonzaga. This agreement concluded the second phase of the Wars in Lombardy. Though provisional, it ushered in a period of relative stability in northern Italy. Diplomatic negotiations resumed the following decades, culminating in the Treaty of Lodi in 1454. The Lodi settlement would underwrite a political balance that fostered cultural and artistic flourishing. Often credited with creating the conditions for the Italian Renaissance, these treaties reshaped the Italian states. They established a framework for diplomatic engagement that influenced European politics.
1428 Republic of Venice Duchy of Milan Republic of Florence House of Gonzaga Wars in Lombardy Treaty of Lodi Italian Renaissance
1506day.year

The cornerstone of the current St. Peter's Basilica is laid.

In 1506, the cornerstone of the current St. Peter's Basilica was laid in Vatican City, marking the beginning of a landmark Renaissance project.
On April 18, 1506, Pope Julius II placed the cornerstone for St. Peter's Basilica in the Vatican. Designed by Bramante, the new basilica aimed to replace the old Constantinian church. The project became one of the greatest architectural undertakings of the Renaissance. Over the next century, masters like Michelangelo and Carlo Maderno would shape its iconic dome and façade. St. Peter's Basilica emerged as a symbol of papal authority and artistic ambition. Its construction influenced church architecture across Europe. Today, it remains one of the largest and most visited churches in the world.
1506 cornerstone St. Peter's Basilica
1518day.year

Bona Sforza is crowned as queen consort of Poland.

Bona Sforza was crowned Queen Consort of Poland on April 18, 1518, strengthening ties between Poland and Italy.
On this day in 1518, Bona Sforza of the prominent Sforza family was crowned Queen Consort of Poland as the wife of King Sigismund I the Old. Born in Bari, she brought Italian Renaissance culture to the Polish court. Her marriage solidified the alliance between Poland and the Italian duchies. During her queenship, she championed economic reforms, land management, and the arts. Bona oversaw improvements in agriculture and trade in her dower lands. Her influence extended well beyond ceremonial duties, shaping the political landscape. She remains a celebrated figure in both Polish and Italian histories.
1518 Bona Sforza queen consort
1521day.year

Trial of Martin Luther begins its second day during the assembly of the Diet of Worms. He refuses to recant his teachings despite the risk of excommunication.

Martin Luther continued to stand firm on April 18, 1521, at the Diet of Worms, refusing to recant his teachings.
On April 18, 1521, Martin Luther faced the second day of questioning at the Diet of Worms. Called by Emperor Charles V, Luther was pressured to retract his writings. He famously declared that he could not recant unless convinced by Scripture and reason. His steadfast position marked a defining moment in the Protestant Reformation. The assembly deliberated on charges of heresy and examined Luther's works. Luther's resolve inspired reformers across Europe and challenged papal authority. Though excommunication loomed, his teachings continued to spread.
1521 Martin Luther Diet of Worms teachings
1689day.year

Bostonians rise up in rebellion against Sir Edmund Andros.

In 1689, residents of Boston rose against Sir Edmund Andros in a colonial revolt that deposed the unpopular governor.
On April 18, 1689, Bostonians rebelled against Sir Edmund Andros, the royal governor of the Dominion of New England. Angered by Andros's authoritarian rule and taxation policies, colonists seized and imprisoned him. This uprising followed news of the Glorious Revolution in England. Local militia and citizens mobilized to restore their previous colonial charters. The revolt effectively ended the Dominion of New England. It demonstrated early American resistance to centralized authority. Similar uprisings occurred in other New England provinces shortly thereafter.
1689 Bostonians in rebellion Edmund Andros
1738day.year

Real Academia de la Historia ("Royal Academy of History") is founded in Madrid.

The Royal Academy of History (Real Academia de la Historia) was founded in Madrid in 1738 to study and preserve Spanish history.
On April 18, 1738, King Philip V of Spain established the Real Academia de la Historia in Madrid. The academy's mission was to research, document, and publish works on Spanish historical heritage. It attracted scholars dedicated to exploring archives, inscriptions, and manuscripts. Over time, it became a leading center for historians and linguists. The institution published important chronicles and edited medieval documents. Its collections grew to include maps, coins, and antiquities. Today, it continues to promote historical studies and cultural preservation in Spain.
1738 Real Academia de la Historia Madrid
1775day.year

American Revolution: The British Army advances up the Charles River in Massachusetts to destroy supplies of American militias, while Paul Revere and other riders rapidly warn the countryside.

During the American Revolution on April 18, 1775, British troops moved to seize colonial arms, while Paul Revere warned militias of their approach.
On the night of April 18, 1775, British forces dispatched troops from Boston up the Charles River toward Concord. Their objective was to destroy stored weapons belonging to the American militias. Meanwhile, Paul Revere and other riders spread the alarm throughout the countryside. Revere's famous ride alerted colonial militias to assemble in force. This clash set the stage for the Battles of Lexington and Concord the next morning. It marked the outbreak of open warfare in the American Revolution. The events galvanized colonial resistance and support for independence.
1775 American Revolution British Army Charles River Massachusetts militias Paul Revere rapidly warn the countryside
1783day.year

Three-Fifths Compromise: The first instance of black slaves in the United States of America being counted as three-fifths of persons (for the purpose of taxation), in a resolution of the Congress of the Confederation. This was later adopted in the 1787 Constitution.

On April 18, 1783, the Congress of the Confederation adopted the Three-Fifths Compromise, counting enslaved individuals as three-fifths for taxation purposes.
On April 18, 1783, the Congress of the Confederation passed a resolution to count each enslaved person as three-fifths of a free individual for taxation. This measure addressed disputes between northern and southern states over apportionment. It represented the first formal compromise on representation and taxation of enslaved people. The policy sought a balance between states with large enslaved populations and those without. In 1787, the Three-Fifths rule was incorporated into the U.S. Constitution. Though politically expedient, it entrenched slavery in the new republic's governance. The compromise remained in effect until the post-Civil War amendments repealed it.
1783 Three-Fifths Compromise Congress of the Confederation
1831day.year

The University of Alabama is founded in Tuscaloosa, Alabama.

The University of Alabama was founded in Tuscaloosa on April 18, 1831, as the state's first public university.
On April 18, 1831, the University of Alabama was chartered in Tuscaloosa, marking the state's first public institution of higher education. Governor John Gayle signed the legislation to establish the university. Its first campus featured a main building modeled after the University of Virginia. Early curricula focused on liberal arts, agriculture, and engineering. Enrollment began modestly but grew rapidly in the following decades. Despite facing setbacks during the Civil War and Reconstruction, it rebuilt and expanded. Today, the University of Alabama is a leading research and academic center in the Southeast.
1831 University of Alabama Tuscaloosa, Alabama
1847day.year

American victory at the battle of Cerro Gordo opens the way for invasion of Mexico.

In 1847, American forces defeated Mexican defenders at the Battle of Cerro Gordo, opening a route into central Mexico.
The Battle of Cerro Gordo occurred on April 18, 1847, during the Mexican–American War. American troops under Major General Winfield Scott advanced through a narrow mountain pass defended by Mexican forces led by General Santa Anna. After intense fighting, U.S. artillery silenced enemy positions on the heights. The victory gave Scott's army a strategic advantage and a clear path to Puebla and ultimately Mexico City. Mexican casualties were heavy, while American losses were moderate. This engagement demonstrated the effectiveness of American military tactics and logistics. It marked a turning point in the campaign and weakened Mexican morale for the remainder of the war.
1847 battle of Cerro Gordo
1857day.year

"The Spirits Book" by Allan Kardec is published, marking the birth of Spiritualism in France.

Allan Kardec’s "The Spirits’ Book" was published in France in 1857, laying the foundation for modern Spiritualism.
First published on April 18, 1857, "The Spirits’ Book" (Le Livre des Esprits) was authored by French educator Allan Kardec. It compiled answers to philosophical questions on life, death, and the nature of spirits, as communicated through mediums. The book outlined the principles of Spiritist doctrine, exploring morality, the afterlife, and human progress. It quickly gained popularity in France and sparked a Spiritualist movement emphasizing scientific study of spiritual phenomena. Kardec’s work influenced religious and philosophical thought throughout Europe and beyond. Over subsequent decades, Spiritism inspired communities, charitable activities, and mediumistic practices worldwide. "The Spirits’ Book" remains a central text for Spiritists and continues to be reprinted in multiple languages.
1857 The Spirits Book Allan Kardec Spiritualism