Monday is New York’s birthday: 350 years ago, on Sept. 8, 1664, English soldiers took control of the Dutch city of New Amsterdam, on Manhattan Island. They soon renamed it after the Duke of York, brother to King Charles II.

Such anniversaries may typically be of interest only to antiquarians, but the occasion resonates so sharply against the backdrop of recent events — the widening divide in American politics, racial and religious intolerance at home and abroad — that reflecting on it might provide a useful perspective on the principles that made us who we are today.

From the moment it was so named, New York City began its ascent as part of England’s expanding empire. Then again, to say that Sept. 8 is New York’s birthday is misleading, for it became a uniquely dynamic place, the model of a modern city, because of what it had been before the English took over. In founding New Amsterdam in the 1620s, the Dutch planted the seeds for the city’s remarkable flowering. Specifically, the Dutch brought two concepts that became part of New York’s foundation: tolerance of religious differences and an entrepreneurial, free-trading culture.

In the 17th century, when it was universally held elsewhere in Europe that a strong society required intolerance as official policy, the Dutch Republic was a melting pot. The Dutch codified the concept of tolerance of religious differences, built a vast commercial empire and spawned a golden age of science and art in part by turning the “problem” of their mixed society into an advantage. Dutch tolerance was transplanted to Manhattan: They were so welcoming that a reported 18 languages were spoken in New Amsterdam at a time when its population was only about 500.

While many economies elsewhere in Europe were still feudal, the Dutch pioneered an economic system based on individual ownership of real estate. That came about because the Dutch provinces occupied a vast river delta, in which land was at or below sea level and therefore constantly under threat. People in those communities banded together to build dams and dikes and reclaim land. The new land was not owned by a king or a church. Instead, the people who had created it divided it and began buying and selling parcels. That incentivized a whole society, fueled the growth of an empire, turned the Dutch into entrepreneurs and made them the envy of other Europeans...