H.M.S. Viper had captured the suspected American slaveship Virginia several days before off the coast of Africa.  The British warship then sought a U.S. Navy vessel and finding the U.S.S. Portsmouth delivered the Virginia into American hands.  The Portsmouth assigned a prize crew and the Virginia was sailed under arrest to the United States.  (By John Osborne) 
Source Citation
Francis Vincent, Vincent's Semi-Annual United States Register.... 1st of January and 1st of July, 1860 (Philadelphia: Francis Vincent, 1860), 109.
    Date Certainty
    Exact
    Type
    Slavery/Abolition

    How to Cite This Page: "Royal Navy turns over suspected American slaveship to the United States Navy," House Divided: The Civil War Research Engine at Dickinson College, https://hddev.housedivided.dickinson.edu/node/31281.