A new research study by Paul Hortenstine and published by NESRI http://nesri.us/nycmayors reveals that over 88% of New York City’s mayors or acting mayors were enslavers or investors in the slave trade between 1665 and 1827.

Completed in 2025 as New York City celebrated its 400^th anniversary, the study focuses on the period from 1665 to 1827, i.e. from when New Amsterdam became New York City until New York State abolished slavery.  However, Hortenstine notes that slavery was interwoven with political power from the city’s earliest days in 1625 under the Dutch and continued even after official emancipation.

From 1665 to 1827, there were 49 mayors or acting mayors: 43 were enslavers or investors in the slave trade. Two additional mayors were connected to slavery after 1827. Hortenstine’s essay includes the following parts:

• Early Merchant Mayors
• Mayoral Slave Trade
• Turmoil and Trials in 1741
• Gradual Emancipation
• New York Abolition

He includes summaries and tables of mayors and their involvement in slavery:

• Timeline of NYC Slavery from Dutch Colony to Civil War
• Names of People Enslaved by Mayors
• Mayoral Involvement in Caribbean Slave Trade
• Mayoral Slave Ship Investments
• Enslaver Mayors and Terms in Office
• Mayoral Administrations Until Emancipation

In addition to enumerating the mayors’ slaveholding and slavery investments, Hortenstine describes how political leaders contributed to the legal underpinning of New York City slavery. They presided over the Common Council that enacted slave codes from the earliest days of the colony. As late as 1818, enslavers were allowed to use the city prison to punish those they enslaved.

The essay relies on numerous and varied records, many previously a part of NESRI and others now added to the index. These include auction terms from 1664, letters from 1698 about the arrival of slave ships, New York City’s census of 1703, a will from 1786, and a register of manumissions from 1810. To find names of the enslaved, he researched documents of sales, wills, court cases, petitions, runaway notices and manumissions.

 In this way, the essay illustrates the importance of NESRI’s core mission, which is to deepen the understanding of enslavement in the northeast United States by collecting, sharing and connecting the many and varied historical records that have previously been disconnected and difficult to access.

Paul Hortenstine is a writer and researcher on public policy and history. He has a M.A. in history from Washington University in St. Louis and a B.A. in history from the University of Missouri-Columbia.