Mr. Camplin was well known for supplying uniforms to the Royal Navy. It was in fact his idea to suggest the use of the peacoat as part of the Petty Officers uniform. Up until then Petty officers had the same uniform as ordinary able seamen.
However, they needed their own uniform to make the distinction but something that would be practical but something that would be more practical than the great coat which senior officers had.
Mr. Camplin than came up with the idea of a jacket, having the same important style as a coat but the practical ease in movement of a jacket. So, the P. officers got their P. Coat (P for Petty in Petty Officer) which then for phonetic reason because the word pea coat. This is the story behind why Mr. Camplin is rightly believed by many to be the inventor of the peacoat.