John Hancock was born on January 23, 1737 in Braintree, Massachusetts. When his father died, he was adopted by his uncle, Thomas Hancock, who worked as a merchant. During his youth, he attended the Boston Latin School.

After graduating, he enrolled at Harvard University and graduated with a degree in business in 1754. He then started working for his uncle's business, meeting with customers and building the company. In 1760, he moved to England and stayed there until 1764, working closely with suppliers for his uncle's company.

When he returned to the United States, his uncle died and he became the sole heir. His uncle's business and fortune became his own and Hancock was soon the richest man in New England. He also met a woman named Dorothy Quincy and the two were married.

When the Stamp Act was passed in 1765, Hancock was furious since it forced all documents to carry a tax stamp. It was eventually repealed on March 18, 1766 after a large degree of resistance. Unfortunately, the British government passed more oppressive acts in the colonies, such as the Townshend Acts.

Under the excessive taxation of the British government, Hancock began to illegally smuggle goods for his business. In 1768, one of his ships, the "Liberty" was seized by British officials in violation of the tax laws. The seizure caused a riot in Boston and only added to the furor.

His growing distaste for British rule led him to use his company's profits to fund anti-British movements in the colonies. On March 5, 1774, he delivered a speech that deeply condemned the British government. Later that year, he was elected as president of the provisional government of Massachusetts.

As president, he directed the formation of minuteman militias that would be prepared to fight British forces in a minute's time. He also directed the boycott of tea from the British East India Company, which subsequently led to the Boston Tea Party. By April of 1775, it became apparent that the British wanted to arrest Hancock and he went into hiding with Samuel Adams in Lexington, Massachusetts. It was there that they heard the cries of Paul Revere, who notified the town that the British military forces were coming.

On May 24, 1775, he was elected president of the Second Continental Congress. In the next month, he chose George Washington to lead the revolutionary Army of the United Colonies. On July 4, 1776, he became the first person to sign the Declaration of Independence and sent a copy to Washington such that he could read it aloud to the troops.

From 1780 to 1785, Hancock served as governor of Massachusetts and frequently worked to supply the revolutionary army. After the war ended, he was elected as the seventh president of the Continental Congress and served until June 6, 1786. In 1787, he was once again elected as governor of Massachusetts and helped to get the federal constitution ratified.

John Hancock died on October 8, 1793, while serving his ninth term as governor of Massachusetts.