In 230 BC, the armies of the powerful Qin Shi Huang looked set to conquer all before them. But one neighboring kingdom, Yan, had other ideas and hatched a devious plan to assassinate him.

The Deadly Attempt to Assassinate Qin Shi Huang (3:05)

China's young emperor, Qin Shi Huang, faced a serious threat to his reign in 238 BC. At the heart of it was his mother, Queen Zhao, and her ambitious lover, Lao Ai.

This Chinese Emperor Was Betrayed by His Mother's Lover (3:35)

Alcatraz has gone from a 'place of evil spirits' in native American lore, to a military prison, to a federal lockup. Today, it's a tourist attraction that draws in people from across the globe.

How Alcatraz Has Changed Throughout History (1:45)

In the 1880s, Frances Ellen Work, a free-spirited American heiress married James Roche, an Irish baron - a template that looks to be repeated with the engagement of Meghan Markle to Britain's Prince Harry.

What Meghan Markle and Frances Work Have in Common (2:47)

From getting sucked into a fighter jet engine to a misjudged landing by an approaching jet fighter, an active flight deck is a minefield of danger and accidents waiting to happen.

This Sailor Got Sucked Inside a Fighter Jet Engine (1:54)

With heavy fog and windy conditions, sailing into San Francisco Bay has long been a hazardous affair. Then, in 1870, things got a lot safer with the construction of the Point Reyes Lighthouse.

This Lighthouse Made Sailing Into San Francisco Bay Safer (1:34)

It's August 26, 1968, and the Democratic National Convention is about to kick off in Chicago. In the background, scenes of turbulence and unrest unfold as antiwar protestors clash with police.

Anti-War Protests Turn Violent at 1968 Democratic Convention (1:33)

William the Conqueror's coronation was marred by a bizarre incident. The guards outside the cathedral mistook the cheers for a riot--so they immediately set fire to the surrounding buildings.

Why a Fire Broke Out at William the Conqueror's Coronation (2:38)

The 1066 battle of Stamford Bridge between Viking warlord Harald Hardrada and King Harold of England was said to be so violent that a giant mountain of bones remained a half century later.

The Violent 1066 Battle of Stamford Bridge (1:51)

It's 1066 and William of Normandy and his massive army of 14,000 men are preparing to cross the English Channel and invade England. But bad weather conditions force them to wait.

How Bad Weather Delayed the Norman Invasion of England (3:10)

Arriving in the Chesapeake Bay, the early American inhabitants' first order of business would have been to craft weapons to defend themselves. They would need them, with terrifying predators like the short-faced bear on the prowl.

Terrifying Mammals That May Have Greeted Early Humans in America (2:32)

On an island off the east coast of Maryland, a stone spearpoint sticking out of a coastal cliff stuns archaeologists. It asks a big question: Could humans have arrived in America 5,000 years earlier than we thought?

The Startling Alternative Theory of How Humans Arrived in America (2:51)

In 1066, the English king Edward the Confessor lay dying in his bed. Three powerful men had strong claims to succeed him, but only Harold Godwinson was close enough to grab power.

How Edward the Confessor's Advisor Seized Power (2:44)

The fast ascension of Harold Godwinson to the English throne in 1066 was greeted with fury by rivals Duke William of Normandy and brutal Viking warlord Harald Hardrada.

Why King Harold's Rapid Coronation Sparked Outrage (2:21)

In the early 1980s, an Indian guru named Bhagwan Shree Rajneesh arrived in the town of Antelope, Oregon and set up a commune for his followers. It was the beginning of an extraordinary sequence of bizarre events.

How the Rajneesh Cult Overran This Oregon Town (1:28)

During the 17th century, the Agooji were a battle-hardened, all-female warrior force that held a special place within the African kingdom of Dahomey. Most were former slaves, with only the bravest and toughest admitted into the fold.

How African Female Ex-Slaves Became Agooji Warriors (2:35)

A gifted student, a Nobel Peace Prize winner, and a civil rights activist. During his short, but remarkable life Dr. Martin Luther King Jr. shaped the nation and the world. Look back at some of MLK's most iconic achievements by the numbers.

By the Numbers: Dr. Martin Luther King Jr. (1:11)

Contrary to popular opinion, the chances of survival in gladiatorial games were higher than originally thought. In fact, only 1 in 9 fights ended in death.

Gladiators Didn't Die As Often As You Think (1:22)

When France sent ambassador Jean-Marie Bayol to Dahomey to secure a deal for the kingdom's rich natural resources, he was greeted by an elite force of all-women warriors known as the Agooji. Their ferocity set the tone for negotiations.

This African Warrior Ceremony Was Highly Intimidating (3:17)

In 2nd century AD, Celtic warrior Ardala is taken to Rome and tossed in a dark dungeon while her captors decide what to do with her. Little does she know that she'll have to fight if she wants to survive.

This Female Gladiator Captive Had to Fight for Her Life (2:39)