Alexander Kent
After Dudley Pope, Kent was the first to pick up the Forester tradition, and was the first of the post-Hornblower authors I personally came across. The series ends with Richard Bolitho's death in action in 1812, but Kent has always been one to go backwards and forwards in his hero's history, so the hope of more books must remain.
Under the pen-name Douglas Reeman Kent has written many other naval stories set outside the Napoleonic era, both historical and contemporary, which are worth reading for a change from the never-ending battle against Napoleon.
