In History, Today on May 20

Portuguese explorer Vasco da Gama arrived at Calicut (now Kozhikode), India, becoming the first European to reach India by sea, marking a significant milestone in the Age of Discovery.

Thomas Thorpe published Shakespeare's sonnets in London, which included 154 sonnets, many of which are considered among the greatest in the English language.

Napoleon Bonaparte reinstated slavery in the French colonies, reversing its abolition during the French Revolution.

President Abraham Lincoln signed the Homestead Act into law, which provided 160 acres of public land to settlers for a small fee, encouraging westward expansion in the United States.

Levi Strauss and Jacob Davis received a U.S. patent for blue jeans with copper rivets, marking the birth of the iconic American garment.

The Triple Alliance was formed between Germany, Austria-Hungary, and Italy, a military agreement that played a significant role in the prelude to World War I.

The eruption of Krakatoa began, leading to one of the most violent volcanic events in recorded history, which would culminate in August with massive loss of life and global climatic effects.

Charles Lindbergh took off from Roosevelt Field in New York, beginning the first solo nonstop transatlantic flight, which he completed the next day in Paris.

Amelia Earhart took off from Newfoundland, Canada, on her solo flight across the Atlantic Ocean, becoming the first woman to achieve this feat.

The first prisoners arrived at the Auschwitz concentration camp in German-occupied Poland, marking the beginning of one of the most infamous sites of the Holocaust.

The Battle of Hamburger Hill during the Vietnam War ended after ten days of intense fighting, with U.S. and South Vietnamese forces capturing the heavily fortified hill from North Vietnamese troops.

The discovery of the HIV virus that causes AIDS was published in the journal Science by Luc Montagnier and his team at the Pasteur Institute in France.

East Timor becomes the first new sovereign state of the 21st century, regaining independence from Indonesia.

The Republic of Montenegro holds a referendum on independence from the State Union of Serbia and Montenegro, with a majority voting in favor.

The first-ever legal same-sex marriages in Latin America were performed in Argentina, marking a significant milestone in LGBTQ+ rights in the region.

A massive tornado strikes Moore, Oklahoma, causing widespread destruction and resulting in 24 fatalities.

The International System of Units (SI) undergoes a major revision, redefining the kilogram, ampere, kelvin, and mole based on fundamental physical constants.

Cyclone Amphan makes landfall in Eastern India and Bangladesh, causing extensive damage and leading to the evacuation of millions of people.

The ceasefire agreement between Israel and Hamas took effect, ending 11 days of intense conflict in the Gaza Strip.