Peter was born enslaved, the son of Amos Newport, Sr., who had been stolen from West Africa when he was young and enslaved by Joseph Billings of Hatfield, Massachusetts. Peter married a woman named Azubah, with whom he had five children. Jonah was born ca. 1760-1765; Peter was born ca. 1765-1770; Eliphalet followed ca. 1770-1771; Amos was born ca. 1771; and an unnamed daughter was born and died in 1775. She was born on April 26 and died on May 13. Azubah had died on May 1, probably from complications giving birth.
Joseph Billings' 1781 will stipulated that "the children of the said Peter, to wit Jonah, Peter, Eliphalet and Amos, shall be manumitted and set free as soon as they shall arrive, respectively, at the age of twenty-one years; in the mean time they shall be subjected to, under the control of, and in the immediate service of, my aforesaid loving cousins David Billing and Silas Billing." Joseph Billings died in 1783, when none of Peter's children had reached the age of 21.
In 1779, while still enslaved, Peter purchased land in Williamsburg, Massachusetts, from Joseph and his nephew David Billings. Peter paid £5 for the land and started a farm. That same year, he married Elizabeth Oliver of Hardwick, Massachusetts. They had two children: Azubah, born ca. 1781, and Rebekah, born ca. 1787. Elizabeth died at age 57 in 1816.
The Newports appear in Williamsburg census reports for 1790-1820. In the first three reports five people are listed in the "all other free persons" category. This would have been Peter, Elizabeth, and most likely Amos, Azubah, and Rebekah. The 1820 census lists one male and one female in the "free colored persons" columns for those aged 45 and up. The male would have been Peter. The female is a mystery, as Elizabeth had already died. One female appears in the column for those aged 14 to 26, and she is also a mystery. Both of these women could have been extended family members.
By the time he made his will in 1819, Peter was a widower with 4 remaining children- Jonah, Amos, Eliphalet, and Rebekah. Peter died in Williamsburg on April 30, 1821. A judge declared his will null and void.