In History, Today on April 12

Sudan's military announces the arrest of President Omar al-Bashir following months of protests against his 30-year rule.

Hillary Clinton formally announced her candidacy for the 2016 U.S. presidential election, making her the first major party candidate to enter the race.

The MV Sewol ferry capsized and sank off the coast of South Korea, resulting in the deaths of 304 passengers, most of whom were high school students. The disaster led to widespread criticism of the South Korean government's handling of the rescue operation.

An earthquake of magnitude 6.9 strikes the Yushu Tibetan Autonomous Prefecture in Qinghai, China, causing significant destruction and loss of life.

Captain Richard Phillips was rescued by the United States Navy after being held hostage by Somali pirates in the Indian Ocean. The rescue operation involved Navy SEAL snipers.

The first episode of the television series 'Mad Men' is filmed, marking the beginning of a critically acclaimed show that would influence television storytelling.

The Venezuelan military overthrows President Hugo Chávez in a coup d'état, leading to his temporary removal from power.

The United States signed an agreement with India to work on civilian nuclear projects together. This agreement marked a significant diplomatic development in U.S.-India relations, underlining a strategic partnership between the two nations.

Euro Disneyland (now Disneyland Paris) opened in Marne-la-Vallée, France, as Disney's second theme park internationally and first in Europe.

The first launch of a Space Shuttle, Columbia, occurred, marking the beginning of the Space Shuttle program by NASA.

Soviet cosmonaut Yuri Gagarin became the first human to travel into space and orbit the Earth aboard Vostok 1.

U.S. President Franklin D. Roosevelt died of a cerebral hemorrhage in Warm Springs, Georgia, and Vice President Harry S. Truman was sworn in as the 33rd President of the United States.

The strongest surface wind gust in the world at that time was measured at 231 mph at the Mount Washington Observatory.

The RMS Titanic officially began construction with the laying of its keel. The construction took place at the Harland and Wolff shipyard.

The Automobile Club de France was established, the first automobile club in the world, reflecting the growing interest and development in motor vehicles by the end of the 19th century.

The Union steel mill was established in Belval, Luxembourg, marking a significant development in the industrial capabilities of the region and contributing to Luxembourg's economic growth.

The American Civil War began with the Confederate attack on Fort Sumter in South Carolina.

The Battle of Les Saintes takes place, in which British forces defeat the French navy, asserting British naval dominance in the Caribbean.

The Halifax Resolves are adopted by the North Carolina Provincial Congress, the first formal call for American independence from Britain.

The formal inquisition of Galileo Galilei by the Roman Catholic Church begins, investigating his support of the heliocentric model.

The Union Flag was adopted as the national flag of Great Britain, symbolizing the union of England and Scotland.

Spanish forces, led by the Duke of Alba, defeat the French at the Battle of St. Quentin during the Italian War of 1551-1559.

The Mongol Empire achieves a significant victory at the Battle of Mohi, also known as the Battle of the Sajo River. This battle was a decisive clash between the Mongol forces led by Batu Khan and Subutai, and the Kingdom of Hungary, led by King Béla IV. The victory allowed the Mongols to overrun the Hungarian plains and subsequently threaten Europe further west.

The Fourth Crusade captured and sacked Constantinople, leading to significant changes in the Byzantine Empire and the establishment of the Latin Empire.

On this day, Holy Roman Emperor Henry V was crowned emperor by Pope Paschal II in Rome. The event took place at St. Peter's Basilica, marking a significant moment in the Investiture Controversy, a conflict between the Papacy and European monarchies over the appointment of church officials.

King Edwin of Northumbria is converted to Christianity by Paulinus, a Roman missionary, marking a significant moment in the Christianization of England.

Anthemius is proclaimed Roman Emperor of the West by Ricimer, a powerful military leader and kingmaker in the Western Roman Empire.

Shapur I becomes king of the Sasanian Empire, succeeding his father Ardashir I. Shapur I is known for his military campaigns against the Roman Empire and his efforts to consolidate and expand the Sasanian Empire.