Historical letters are of inestimable value to historians, sociologists, and archaeologists. They offer a peek into how people thought and what they felt about important issues. They provide insight into past events, weather patterns, eating habits, cultural traditions, and more. They help archaeologists better understand artifacts they have discovered and provide clues that could lead to future discoveries.

Even so, the power of historical letters goes beyond just providing knowledge of the past. Letters have radically changed the world many times, contributing to the creation of new civilizations while bringing about the end to old customs and practices. Perhaps the most visible example of this is the change brought about by the letters found in the New Testament of the Bible. Thanks to their influence, polytheism became a thing of the past in much of the Western World. They also brought about an understanding of basic human rights and put an end to customs such as human sacrifice and gladiatorial fights.

After the invention of the printing press, letter-writing become even more prolific, and many famous people wrote letters to share their thoughts and feelings before taking drastic action or making their views widely known. Henry VIII’s letter to Ann Boleyn, for instance, not only conveyed his feelings to her but cemented these feelings in his own heart. As a result, he declared himself the head of England’s church, forever separating his country from Papal control. Charles Darwin sent a steady stream of letters to his good friend, botanist Joseph Dalton Hooker, to explain his thoughts on natural selection years before publishing On the Origin of the Species.

It was a mother’s letter that convinced a little-known member of Tennessee’s House of Representatives to vote in favour of ratifying the nineteenth amendment that would give women the right to vote. State Rep. Harry Thomas Burn was known for his anti-suffragist views, but his mother’s letter made him change his mind and vote in favour of suffragist rights. Thus, Tennessee became the thirty-sixth state to vote in favour of the nineteenth amendment, ensuring its passage into law. Years later, another letter penned to a politician effected change on a vastly different scale. Albert Einstein wrote to President Franklin Delano Roosevelt to urge him to develop an atomic bomb before the Nazis did. The result was that the U.S become the first nation to successfully create nuclear weapons. These were used to bring an end to World War 2 but also set off a nuclear arms race that put the world at risk of nuclear annihilation. On a more positive note, Martin Luther King’s “Letter from a Birmingham Jail” rebutted the notion put forward by some that protests were not the answer to racism in the United States and encouraged civil rights activists to continue the fight for equal rights. Their efforts eventually led to the passage of the Civil Rights Act in 1965.

While these historical letters are some of the most widely known letters in the world, they are not the only ones to bring about significant change. In fact, it would be impossible to trace all the changes that occurred in world history as a result of letters that changed the opinions of key individuals who went on to share their changed opinions with others. At the same time, a letter does not have to impact world history to be meaningful. Research has found that nearly 70% of individuals would appreciate a handwritten letter more than a text, tweet, or Facebook message, making it clear that letters are still as powerful and meaningful as they have been since the onset of civilization.