Admiral of the Fleet Sir James Elphinstone Erskine, was a Royal Navy officer. As a junior officer he served on the North America and West Indies Station. This was a difficult time in relations between the United Kingdom and the United States following the Trent Affair, an international diplomatic incident that occurred during the American Civil War when the United States Navy frigate USS San Jacinto intercepted the British mail packet RMS Trent.

Admiral of the Fleet is a five-star naval officer rank and the highest rank of the Royal Navy, formally established in 1688. The five-star NATO rank code is OF-10, equivalent to a field marshal in the British Army or a Marshal of the Royal Air Force. Apart from honorary appointments, no new admirals of the fleet have been named since 1995, and no honorary appointments have been made since 2014.