According to Ukawsaw Gronniosaw's autobiography, the Rev. Theodorus Jacobus Frelinghuysen purchased Gronniosaw from his former enslaver named Vanhorn for 50 pounds. As the result of this sale, Gronniosaw moved from Vanhorn's household in New York City to Frelinghuysen's home in Raritan, New Jersey.
See p. 12 in Gronniosaw's book:
"Mr. Freelandhouse, a very gracious, good Minister, heard it, and he took a great deal of notice of me, and desired my master to part with me to him. He would not hear of it at first, but, being greatly persuaded, he let me go, and Mr. Freelandhouse gave £50. for me."
According to Ukawsaw Gronniosaw's autobiography, the Rev. Theodorus Jacobus Frelinghuysen manumitted Gronniosaw in his will and also left him 10 pounds. At the time of Frelinghuysen's death around 1747, Gronniosaw had been enslaved in the Frelinghuysen household for nearly two decades. After his manumission, Gronniosaw continued working for the Frelinghuysen family as a servant for several years.
See p. 18-19 in Gronniosaw's book:
"my temporal comforts were all blasted by the death of my dear and worthy Master Mr. Freelandhouse, who was taken from this world rather suddenly: he had but a short illness, and died of a fever. I held his hand in mine, when he departed; he told me he had given me my freedom. I was at liberty to go where I would.--He added that he had always pray'd for me and hop'd I should be kept unto the end. My master left me by his will ten pounds, and my freedom."
In November 1752, slave trader Philip Livingston offered a reward of 3 pounds for the capture of an African man who escaped from Livingston in New York City. The man did not speak any English or Dutch (the primary European languages in eighteen-century New York) because he was only recently brought to New York City from Africa. This incident took place 14 years before Philip Livingston would became a charter trustee of Queen's College.
The advertisement offered a description of the man's African hairstyle: "his hair or wool is curled in locks, in a very remarkable manner." Livingston also referred to the man as a "a very likely lusty fellow." In eighteenth-century America, the term "likely" meant good looking, while the term "lusty" meant healthy and vigorous. Thus the words "a very likely lusty fellow" suggest that the freedom seeker was a strong and healthy man in the prime of his life.
Livingston supposed that the freedom seeker made his way toward the woods near Harlem, which was at that time a small village north of New York City on the Island of Manhattan (the Harlem area has since then been incorporated into New York City as a neighborhood north of Central Park).
The following is a transcript of the advertisement from the New-York Gazette issue of November 6, 1752:
"Run away from Philip Livingson [sic], of New York, on the 28th of October last; a Negro Man, lately imported from Africa, his Hair or wool is curled in locks, in a very remarkable manner; he is a very likely lusty fellow, and cannot speak a word of English, or Dutch, or any other language but that of his own country. He was seen last Monday on New York Island, and is supposed now to be in the Woods near Harlem. whoever takes up said Fellow, and delivers him to his said master shall receive THREE POUNDS as a reward, from PHILIP LIVINGSTON."
Phill, a Black woman or girl, ran away from Samuel Hallett of Hallett's Cove (present-day Astoria, Queens, New York) around June 1763. Her age at the time of this event is unknown. Phill's primary enslaver was James Neilson of New Brunswick, New Jersey, and it is unclear how long Phill was living with or working for Samuel Hallett in New York prior to her escape. A runaway advertisement offering a reward of twenty shillings for Phill's capture and return was published in the newspaper called The New-York Gazette, or, the Weekly Post-Boy on June 16, 1763. In addition to Samuel Hallett and James Neilson, the ad mentioned that Phill could be brought to James Abeel in New York if she was captured. James Abeel was the husband of James Neilson's niece Gertrude Neilson Abeel, and evidently he was ready to assist James Neilson in capturing Phill.
The full text of the runaway ad follows below:
"RUN away, last Night, from Samuel Hallett, of Hallett's Cove, a Negro Girl, named Phill, belonging to James Neilson, Esq; of New-Brunswick, about five Feet high, well made, and pretty Black. Whoever will take up and secure the said Wench, or bring her to said Hallett, or James Abeel, in New-York, or to her said Master, at New-Brunswick, shall receive TWENTY SHILLINGS Reward, and all reasonable Charges, by either of the above mentioned Persons."
Ukawsaw Gronniosaw published his autobiography in approximately 1772 in England where he lived by this time as a free man. In his book, he recounted the details of his life, including his years in slavery in the Raritan River Valley in New Jersey.
The title of the book is:
A Narrative of the Most Remarkable Particulars in the Life of James Albert Ukawsaw Gronniosaw, an African Prince, As related by Himself.
This is one of the earliest autobiographies published by a formerly enslaved person.
Ukawsaw Gronniosaw died on September 28, 1775, several years after publishing his autobiography where he recounted his life in slavery in the home of the Rev. Theodorus Jacobs Frelinghuysen in the Raritan River Valley in New Jersey. Gronniosaw was approximately 65 to 70 years old when he died.
The following is the complete text of Gronniosaw's obituary published on October 2, 1775, in the newspaper called Chester Chronicle, or, Commercial Intelligencer:
"On Thursday died, in this city, aged 70, James Albert Ukawsaw Gronniosaw, an African prince, of Zoara. He left the country in the early part of his life, with a view to acquire proper notions of the Divine Being, and the worship due to Him. He met with many trials and embarrassments, was much afflicted and persecuted. His last moments exhibited that cheerful serenity which, at such a time, is the certain effect of a thorough conviction of the great truths of Christianity. He published a narrative of his life."
Rev. Jacob Rutsen Hardenbergh (1736-1790), first president of Queen's College (later Rutgers), mentioned a Black man in a letter to his father Col. Johannes Hardenbergh (1706-1786) written on December 6, 1777. The letter was sent from Hardenbergh's parsonage in Raritan (present-day Somerville), and was likely sent to Rosendale, NY, where his father lived. Written in Dutch, the letter states "Schrijve dese wynige in haast, wijl de neger gereet maakt om af te gaan." The English translation is: "Writing these words in a hurry while the negro is getting ready to leave." These words most likely refer to an enslaved Black man who was working at Hardenbergh's parsonage at this time; the man's name is not recorded.