Midshipmen are the lowest rank in the Royal Navy. During the days of sailing vessels, from the 17th through the 19th centuries, a midshipman was an apprentice officer. The word derives from the location of ship, amidships, where they were berthed. The first published use of the term Midshipmen was in 1662, and from 1677 all candidates for commissioned rank in the Royal Navy required previous service as a midshipman. Midshipmen is an English term, the equivalent term in Spanish is guardia marina. In French, the similar term garde marine was renamed in Republican France to aspirant, and again in 1814 élèves de la marine.
At the height of the Age of Sail during the Napoleonic era (1793 - 1815), most midshipmen started their sailing career around the age of 11 or 12. The regulations in the Royal Navy demanded that no-one 'be rated as master's mate or midshipman who shall not have been three years at sea'.. There were several ways of getting around this requirement. Since most Midshipmen were from the landed gentry or had family connections with sailing ships, they could use their standing to have their name placed on a ship's books. A notable example was Thomas Cochrane, whose uncle had him entered at the age of 5, and his name was carried on various ships until he was 18 and received his commission.