What was the lowest rank to command a post ship during a battle?
Short answerA midshipman might inherit command after casualties, while the most junior officer deliberately sent into battle in command would normally be a senior lieutenant promoted acting captain.
NotesA midshipman could inherit command near the end of a battle, when the remaining officers were either completing a victory or approaching surrender. Before an action, the most junior deliberate appointment described is a senior lieutenant promoted to acting captain. An admiral knew which first lieutenants had the longest service and could move one to a ship whose captain had fallen ill. If the officer already aboard had similar experience, perhaps only a few months less, the preference was to promote that officer and preserve the existing chain of command.