The 1918 outbreak of the H1N1 strain of influenza, popularly known as the Spanish flu, killed more people worldwide than World War I, which ended the same year. It infected nearly one-third of the world's population and killed 10 percent of those it struck. In its wake, schools and businesses closed, hospitals became overwhelmed, and the sick spilled out into makeshift care centers in public spaces. Policemen, public transportation workers, and everyday citizens in face masks were a common - and eerie - sight.

During the late years of the 18th century, the spirit of Enlightenment thinking and revolution were in the air. The world was changing, moving away from ingrained beliefs about religion, reason, society, and the rights of the individual and turning more toward the laws of nature as interpreted by the scientific method. Nowhere was the influence of this radical new way of thinking more apparent than in France, and the upheaval this caused would come to bloody fruition in the form of revolution. 

Many ancient civilizations are described as mysterious, but none provide as many puzzles and unanswered questions as the Olmecs. These people arrived in lands near the Gulf of Mexico around 1500 BCE and brought with them entirely new concepts in terms of engineering, agriculture, and religion. The problem is we have no idea where they came from or how they developed these new ideas.

World War I, or the Great War, was believed to be "the war to end all wars". Because of the incredible extent of destruction and the staggering number of wounded and dead, even those who lived through it could scarcely comprehend its horror. Beginning in 1914, alliances between powerful nations soon plunged the world into a global conflict. Fighting - including miserable trench warfare - broke out in practically every corner of Europe and spread around the world to Africa, Asia, and the Middle East.

The Great Famine which afflicted Ireland from 1845 to 1849 was one of the most catastrophic events in Europe during the 19th century. More than one-quarter of the population of Ireland died of starvation or associated disease, or were forced to emigrate...The Great Famine left a legacy of distrust and animosity between large segments of the population of Ireland and Great Britain, and this in part led to the movements which finally produced Irish independence.

The saga of the Vikings rises and falls on the banks of history, ebbing and flowing with popular opinion and whimsical anecdotes. The Vikings are routinely typecast and labeled anywhere from bloodthirsty tyrants to valiant heroes. They have been condemned as pirates and praised as explorers. We have all heard the stories of the fierce warriors with long ships and horned helmets storming onto the shores of medieval Europe - but who were these men really?  

Alexander the Great. A boy, groomed for greatness from the earliest age, who would put his stamp on the world for generations to come. A man who sought immortality and achieved it in just 10 years. A soldier whose genius for strategy and tactics is still studied in the modern world. A ruler who understood how to win the hearts and minds of his subjects. This is the story of a Titan of the ancient world, a man who rose but, though he died, never truly fell.

The Crusades are the prototype and epitome of the Holy War. The fight to take control of the city of Jerusalem, believed to be the most sacred Holy City to two distinct religions of Christianity and Islam, has lasted far longer than the two centuries of the Crusades, and its reach has extended far further than Europe and the Middle East.  

Whether you approve or disapprove, globalization is an inescapable feature of the modern world. Trade between nations and continents is now commonplace, and this exchange of goods is inevitably accompanied by the exchange of ideas and cultures. This is not, as you might expect, a new phenomenon. A series of trade routes which were first established almost 2,000 years ago provided one of the first examples of intercontinental trade. 

The Renaissance, or rebirth, was a period of time when Europeans began to question what they had been told was sacrosanct. Through art, inventions, science, literature, and theology, the separate nations of the European continent sought answers that the Roman Catholic Church was unwilling, or perhaps unable, to offer. It was a triumph of the human spirit and a confirmation of human ability, even as it affirmed the willingness of men and women to die for the right to think freely.  

What do you think of when you consider the Middle Ages? Knights in armor and damsels in distress? Vikings plundering monasteries? Religious dissenters burning at the stake? The dead bodies piling up as war, famine, and plague devastated Europe? Think again. While all these are part of the tapestry of the medieval era, the threads of politics, personality and war, culture, religion, education and the arts are vastly more intricate and fascinating. 

The Great Depression was one of the most trying eras in American history. All aspects of the US were affected. After the stock market crash of 1929, the nation was thrust into a decade of turmoil and change - in government, the economy, and culture. Many of the changes brought about by the Great Depression remain today.   

In 1642, King Charles I and the elected Parliament of England went to war over the future of the Stuart kingdom. Over the next nine years, three civil wars would be fought, devastating the populations of England, Scotland, and Ireland. With the authority of the monarchy, the freedom of Parliament, and the power of religion at stake, the English Civil Wars decided the future of Great Britain and influenced the future of politics around the world.

Founded at the dawn of the 17th century as European nations were establishing global empires, the English East India Company would become a vital part of burgeoning British supremacy. Begun as a joint-stock company for trade with the East Indies, this organization would evolve into one of the world's first capitalistic corporations.

From its beginnings as a loosely definable group of philosophical ideas to the culmination of its revolutionary effect on public life in Europe, the Age of Enlightenment is the defining intellectual and cultural movement of the modern world. Using reason as its core value, the Enlightenment believed that progress and the betterment of the human condition was inevitable.