It all started in the early 1600s when the Dutch had a colony called "New Amsterdam" on what is now Manhattan. It was, even then, a region devoted to commercial enterprises, with much trading going on. When the Dutch began to fear trouble from English colonies to the north, they built a wall to protect themselves. Unfortunately for the Dutch though, the attack did come, but by sea. New Amsterdam became New York and in New York City, you'll now find Wall Street where the wall used to stand.
New York's commercial spirit flourished, as did the city itself. Philadelphia was also thriving, and that's where America's first stock market was established in 1790. The New York Stock Exchange (NYSE) came soon after. The NYSE traces its origins to some traders meeting regularly under a buttonwood tree in 1792. It was formally organized in 1817.
Today, the term "Wall Street" often refers to the financial establishment. Much of America's (and even the world's) financial institutions are based in New York, on and around Wall Street, but you'll find many that are located elsewhere.
You'll gain more insights into the history of the American stock market in Peter Lynch's (and John Rothchild's) book Learn to Earn, and in Peter Bernstein's Capital Ideas: The Improbable Origins of Modern Wall Street. The New York Stock Exchange also has an interesting area detailing its history.
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