The Royal Caroline was built in 1700 and was first named Peregrine. However, two years after the accession of George I (1716) she was renamed the Caroline and in the reign of George II (1727) she was extensively refitted and named the Royal Caroline.
She was 'ship-rigged' (i.e. three-masted) and was the biggest and most seaworthy of the Royal Yachts of George I and George II. Both monarchs, particularly George I, had to make regular visits to the continent and most of the sea crossings were made in the Royal Caroline, usually accompanied by other yachts and one or two naval vessels.
The present painting, signed by L.D. Man, probably illustrates such a voyage round about 1727-1730. The smaller vessel escorting is thought to be the yacht Katharine. The Royal Caroline is not flying the Royal Standard (which means that the sovereign is not on board), thus indicating that she might be on her way to pick him up at a continental port.
L.D. Man and Peter Monamy both did many portraits of the Royal Caroline, as she was the favorite Royal Yacht and therefore a desirable subject for marine portraiture.