The dignified white-haired gentleman who appears on the posters for “Slavery in New York,” the New-York Historical Society’s inspired new multimedia show, was named Caesar. Apparently, he had no other name. Born a slave in New York, he served three generations of Knickerbocker aristocrats, and when an unknown photographer took his daguerreotype in 1851, he was about 114 years old. Caesar’s is only one of the many powerful images in the nation’s first major exhibit sponsored by a major museum to illuminate Manhattan’s central part in “the peculiar institution” of American slavery.

From the 17th century through the early 19th, New Yorkers bought, sold, and transported slaves, financed and insured slave ships, and dealt in the sugar, tobacco, coffee, and cotton that slaves produced. The city’s role as a center of slavery and the slave trade has until now been largely forgotten. This forgetfulness is somewhat understandable: After all, New Yorkers peacefully abolished slavery in 1827, and New York’s slavocracy was never romanticized through equivalents of “The Birth of a Nation” or “Gone With the Wind.” But it’s also likely that until recently historians pushed the stories of New York’s slaves to the margins of scholarship. And perhaps some of New York’s wealthiest families would rather forget the foundation of their inherited riches on the agonies of the Middle Passage.

So this fascinating exhibit is utterly necessary and long overdue.

Slavery was here from the beginning. The Dutch West India Company settled African slaves in Manhattan as early as 1626. Manhattan was literally the company’s town, and its slaves built the city’s first infrastructure. African slaves built the wall along Wall Street, the canal along Canal Street, the great fortress at the Battery, the first Trinity Church, and the city’s roads and streets. After seeing this exhibit, the argument that our city’s prosperity was founded on the unpaid toil of African slaves seems less like hyperbole and more like common sense.

Intriguingly, the exhibition notes that the Dutch to some extent acknowledged the slaves’ humanity, permitting them to marry, form families, own property, and even litigate. As early as 1644, slaves were permitted “half-freedom,” by which they were released on the condition that they provide on-demand services to the Dutch West India Company and pay an annual tax due in cash or kind. The children of “half-free” slaves, however, were still born slaves.

By contrast with the Dutch, the British dehumanized slaves, defining them as property on par with horses or dogs. The exhibit quite graphically describes the increasingly draconian laws for slave control enacted between 1665 and 1730. Slaves were prohibited from marrying, owning property, or congregating in groups larger than three, and faced horrendous punishments for conspiring against the whites.

New York’s slaves repeatedly rebelled against their British masters. In 1712, rebellious Africans killed eight whites and seriously injured more than 20; many rebels committed suicide rather than surrender. On March 18, 1741, slaves allegedly burned the governor’s residence and numerous other homes and businesses. A controversial investigation led by Justice Daniel Horsmanden blamed the fires on a conspiracy of slaves aided by white accomplices; subsequent trials, featuring evidence obtained through torture, resulted in the execution of 30 slaves. Even some of Horsmanden’s contemporaries questioned his findings, arguing he had sought to justify the executions rather than find the truth.

During the 18th century, as many as one-fifth of all New Yorkers were black, and over 40% of the city’s households owned slaves. Some of the city’s most distinguished families profited from slave trading: Schuylers, Beekmans, Livingstons, and Van Cortlandts, to name only a few. By the time of the Revolution, New York was second only to Charleston, S.C., as an urban center of slavery.

Slaves flocked to New York after the British promised freedom to any slave who supported the Crown during the Revolution. Many volunteered for military service and fought against American troops. Some 3,000 blacks left with the British when they evacuated New York in 1783. A particularly compelling item on display at the Historical Society is a page from the Book of Negroes, a British government ledger recording each freed slave by name and former owner. It lists Deborah Squash, whose former owner, General George Washington, unsuccessfully demanded that the British return his runaway property.

Slavery faded away in New York after independence. The New York Manumission Society, formed by John Jay, Alexander Hamilton, and other distinguished New Yorkers, forcibly advocated slavery’s abolition while providing legal assistance to slaves and free blacks. From 1799 to 1817, the State Legislature gradually granted freedom to slaves and their children until, on July 4, 1827, slavery was peacefully abolished in New York. As the exhibit notes, the newly freed slaves did not celebrate until July 5, for fear that drunken whites celebrating Independence Day might attack them.

The exhibit successfully uses video reenactments, audio narratives, and interactive videos to communicate the daily reality of slavery in New York: slaves living in the attic or the cellar, preparing food, cleaning chimneys, and emptying the chamber pots. They effectively show the emergence and survival of the slaves’ independent culture, which was transmitted from one generation to the next, and of which white society remained largely unaware.

The exhibit also makes compelling use of original documents and newspapers, many from the Society’s archives. They show how easily slavery’s institutionalized cruelty became just another means of doing business. The ledger kept by the captain of the slave ship Rhode Island, owned by the Livingstons (one of whom would later sign the Declaration of Independence), transforms the purchases of human beings into so many account entries. Newspaper advertisements for “Negroes to be Sold: A Parcel of young able-bodied Negro Men…” make slave auctions seem as ordinary as shoe sales.

Last, numerous paintings and prints distinguish how foreigners and white New Yorkers perceived the black presence in early 19th century New York. For the latter, blacks were simply not part of the landscape. But foreign artists recorded with clear eyes, capturing the ubiquity of slavery and of black workers in their sketches, watercolors, and paintings. Nicolino Calvo’s “Chimney Sweep at Rest” (1840-44) shows an exhausted workingman and the Baroness Hyde de Neuville’s “Corner of Greenwich & Dey Street” (1810) captures a line of black women drawing water from a public well.

“Slavery in New York,” the largest single exhibit ever mounted by the New-York Historical Society, is even more audacious than its 2004 exhibit on Alexander Hamilton – and every bit as essential to understanding the American experience.