John Frederick Radloff was born in 1749 in Germany. It is not clear when he came to this country, but he eventually settled in Rehoboth, MA. On November 7, 1780, he married Sarah Medbury, daughter of John and Annie (Camp) Medbury. Together they had at least 6 children:  Sarah, Hannah, Dorrance, Davis, Betty, and Charles. Four of their children died in childhood.  Charles died at sea at the age of 22 leaving Sarah to be the only child to live to full adulthood. 

Radloff was a surgeon during the American Revolutionary War for more than four years. In December of 1777, he was appointed to the frigate Providence II, a vessel of war under the command of Commodore Abraham Whipple. The Providence II, a 28-gun frigate, built by Silvester Bowes at Providence, RI, by order of the Continental Congress, was launched in May 1776. The ship had been blockaded in the Providence River by the British for more than a year, when on the night of April 30, 1778, it ran the blockade. They fought through the British Fleet, which then had control of Newport Harbor and the waters of Narragansett Bay. From there, they proceeded to France to procure guns and supplies for Continental Navy vessels under construction. The ship returned to America, landing in Portsmouth, NH on October 15, 1778 and arriving in Boston in November. The Providence II made several other cruises during that time and the following year, when she was ordered to go to the relief of Charleston, South Carolina. In the spring of 1780 the ship was captured by the British when the city fell on May 12 and Radloff was made prisoner and remained a prisoner until the close of the war in 1783. He then returned home on a parole of honor. 

Not much is known about his life after service. Records indicate that he remained in Rehoboth and resumed his work as a surgeon. Deed research indicates that the Radloff family lived in the house at 42 Pleasant St. in Rumford. He died on June 13, 1808 at the age of 59.  He is buried in Newman Cemetery in Rumford, RI. His gravesite is marked with a slate stone which was carved by Samuel Tingley Jr. His epithet reads:

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