The Four Days Battle was fought from June 11 - June 14, 1666 during the Second Anglo-Dutch War. It remains one of the longest naval engagements in history.
The English fleet, commanded by George Monck, Duke of Albermarle, was outnumbered by the Dutch. The battle ended only after both fleets had expended all ammunition.
The Netherlands' legendary Admiral Michiel de Ruyter inflicted large damage on the English fleet. The English lost ten ships, thousands of men and two admirals: Sir Christopher Minns and Sir William Berkeley. The English ship HMS Sovereign of the Seas was unable to join the battle due to lack of sailors to man her.
It was the largest navy battle in this sea war. However the outcome proved inconclusive: two months later the recuperated English fleet challenged the Dutch fleet again, at North Foreland in the St Jamesí Day Fight. This time the Dutch were defeated.