8 Nov. 1820–13 Feb. 1866
John Randolph Winslow, physician, the first child of Nathan and Margaret FitzRandolph Winslow, was born on his father's plantation in Perquimans County. Because his family belonged to the Society of Friends, he very possibly was sent to the Friends' Boarding School at Providence, R.I. (later Moses Brown School). In 1838 he entered Haverford School in Pennsylvania (now Haverford College), from which he was graduated in 1840.
Winslow was a highly cultured man, and it is thought that on leaving Haverford he taught at Belvidere Academy. Soon, however, he began to study medicine at the University of Pennsylvania, from which he received an M.D. degree in 1846. Returning to his home, he established an office on his father's estate and remained some years in that locality. About 1851 he moved to Baltimore, where he continued to practice medicine until his death. He was also professor of materia medica in the Maryland College of Pharmacy (now the Department of Pharmacy of the University of Maryland). A nephew, Randolph Winslow, remembered being present at one of his lectures in 1865, although he was too young to understand the subject of his discourse. The late Professor Charles Gaspari, of Baltimore, told Randolph Winslow that he was a pupil of John R. Winslow at the time of his death.
Winslow invested extensively in western lands. Although he did not realize much from these transactions, the members of his family later profited when the land was sold. He died in Baltimore, reportedly from typhus fever that he had contracted from African American patients. At his death he was unmarried and intestate, his father being his only heir. His nephew Randolph, who was living with him at the time, was the only member of his family present at his funeral.
In personal appearance, he resembled his brother Dr. Caleb Winslow so closely that they were often mistaken for each other, although John had darker coloring.