I’ve heard many times about how the Dutch bought Manhattan for an extremely good price. But I also know Wall Street is named for a wall that used to be at that location that was for protection from Native Americans. But why did they have to build the wall if the Native Americans had traded away the island willingly? Is there more to the story than I’ve heard?
The wall was in fact built in response to the threat of the English, on the orders of Peter Stuyvesant in 1653. I'm unsure where the claim it was built to keep out Indians comes from, but it can be found all over the internet on blog posts and other websites about the city's history. As one of those sites claims, it's possible settlers built up some fences in the vicinity of the eventual wall during a period of conflict with Indians. That seems plausible enough but I haven't seen any actual evidence to back it up.
But this maybe gets at the larger point, which is that the colony of New Netherland (and the town of New Amsterdam that became New York) absolutely had a violent history with its Indian neighbors. That history wasn't always pure animosity, however, especially in the earliest years of the settlement when the two groups in many ways relied on each other.
This goes back to the first part of your question, Peter Minuit's famous 1626 "purchase" of Manhattan from the Lenape. There are different interpretations of what exactly those Indians understood the deal to mean, but in addition to the right to use the land, at minimum it included an alliance in which the Dutch agreed to help defend the Lenape from their enemies. This alliance would be tested at various times in the colony's early history, but it didn't fall apart until Kieft's War in 1643.
Willem Kieft was Stuyvesant's predecessor as Director of New Netherland. Kieft viewed the neighboring Indians and the alliance as a nuisance, and grew to despise them as minor incidents between the Dutch and Indians became more frequent. As new Dutch settlers arrived and more farms popped up, livestock would occasionally wander into an Indian farm and ruin the crops. Indians would then kill some livestock, etc. In response, Kieft's first move as director was to levy a tax on the Lenape for his protection. But when this was instantly identified as a breach of their alliance, Kieft grew angry and began to assert his power by finding excuses to torture and kill Indians in the surrounding area.
This culminated in two massacres on the night of February 25, 1643.
Tappan and Wiechquaesgeck refugees from north of Manhattan, fleeing attacks from Mohicans from further north, had arrived at the fort in New Amsterdam for protection while others took refuge in the nearby settlements of Pavonia and Corlears Hook. This case illustrates that, quite contrary to the popular myth, New Amsterdam up to this point served as a place to protect local Indians, not to keep them out.
However, because a Wiechquaesgeck boy had killed a Dutch settler, Kieft took this as his chance for revenge. Against the wishes of his advisers and under the cover of night, Kieft ordered two regiments of soldiers to slaughter men, women and children alike in the encampments. Write Burrows and Wallace, "The heads of more than eighty victims were brought back to New Amsterdam for display, and Kieft made a little speech congratulating his forces on their valor."
From there the region's Lenape bands grouped together and commenced a years long war against the colonists, in which hundreds of Dutch and thousands of Indians died.
When thinking about those years of conflict the idea of a fortification keeping Indians out certainly makes sense. But the actual wall as clearly seen at the edge of town in the famous Castello Plan map, came almost a decade later thanks to a different threat.
Kieft was replaced with Stuyvesant for his mishandling of the colony in 1647. By this time, the New England colonies to the north had also fought and won their own deadly war against the Indians, and had pushed their way south toward the shores of Long Island. Over the next several years many English settlers left the bounds of New England looking for a new start and began setting up new villages on land claimed by the Dutch. While some of the towns closest to Manhattan, like Flushing, remained under Dutch control, they nevertheless hosted large English populations. And because Stuyvesant, during his reign, had constantly tested the limits of his power and the patience of the citizens, some towns were in open revolt against his rule.
These events coincided with the onset of war between the two nations in Europe, and rumors began swirling in New Amsterdam that the English had their sights set on capturing the town. Perceiving an imminent threat of English invasion, it was at this time that Stuyvesant ordered the construction of a wooden stockade along the northern border of the town, along the present-day site of Wall Street. The town added towers and further reinforced the wall over the next decade.
It probably doesn't need to be noted, but the wall of course did not prevent the English from taking New Amsterdam. Besides, they didn't march down over land from New England, they sailed in from the south and took the town without firing a shot.
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