Jack Aubrey

John "Jack" Aubrey, JP MP FRS is a fictional character in the Aubrey–Maturin series of novels by Patrick O'Brian. The series portrays his rise from lieutenant to rear-admiral in the Royal Navy during the Napoleonic Wars. The twenty (and one incomplete draft)-book series encompasses Aubrey's adventures and various commands along his course to flying a rear admiral's flag.

Most of his naval battles and adventures are drawn from actual Royal Navy history. Several of his exploits and reverses, most importantly those in the plots of Master and Commander, The Reverse of the Medal and Blue at the Mizzen, are directly based on the chequered career of Thomas Cochrane.

Besides reaching the peak of naval skills and authority, Aubrey is presented as being interested in mathematics and astronomy, a great lover of music and player of the violin, a hearty singer and is generally accompanied by his friend and shipmate Stephen Maturin on the cello. He is noted for his mangling and mis-splicing of proverbs, sometimes with Maturin's involvement, such as “Never count the bear’s skin before it is hatched” and “There’s a good deal to be said for making hay while the iron is hot.”