Post-captain

Post-captain is an obsolete alternative form of the rank of captain in the Royal Navy.

The term served to distinguish those who were captains by rank from:

Once an officer had been promoted to post-captain, his further promotion was strictly by seniority; if he could avoid death or disgrace, he would eventually become an admiral (even if only a yellow admiral).

In the Royal Navy of the time, an officer might have a rank, but not a command. Until the officer had a command, he was "on the beach" and on half-pay. An officer who was promoted from commander was a captain, but until he was given a command, he was on half-pay. Once the captain was given a command, his name was "posted" in the London Gazette.

An officer "took post" or was "made post" when he was first commissioned to command a rated vessel — that is, a ship too important to be commanded by a mere commander. Usually this was a rated vessel, but occasionally an unrated vessel could in some cases be commanded by a post-captain. Being "made post" is portrayed as the most crucial event in an officer's career in both Forester's Horatio Hornblower series and O'Brian's Aubrey-Maturin series.

A junior post-captain would usually command a frigate or a comparable ship, while more senior post-captains would command larger ships. An exception to this rule was that a very junior post-captain could be posted to command an admiral's flagship, which was almost always a large ship of the line. The admiral would usually do this to keep his most junior captain under close observation, and subject to his direct supervision. Captains commanding an admiral's flagship were called "flag captains". One example of an admiral appointing a junior post-captain to command his flagship in this way is the appointment of Alexander Hood to the command of HMS Barfleur, flagship of his brother, Admiral Sir Samuel Hood.

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