Henry Grace à Dieu, also known as Great Harry, was an English carrack or "great ship" of the King's Fleet in the 16th century, and in her day the largest warship in the world. Contemporary with Mary Rose, Henry Grace à Dieu was even larger, and served as Henry VIII's flagship. Built by William Bond under the direction of Robert Brygandine, she had a large forecastle four decks high, and a stern castle two decks high. She was 165 feet (50.29 m) long, measuring 1,000 tons burthen and having a complement of 700 men. She was ordered by Henry VIII, probably to replace Grace Dieu, which had been destroyed at the Battle of Saint-Mathieu in August 1512. At a time of naval rivalry with the Kingdom of Scotland, her size was in response to the Scottish ship Great Michael, which had herself been the largest warship when launched in 1511.

A carrack is a three- or four-masted ocean-going sailing ship that was developed in the 14th to 15th centuries in Europe, most notably in Portugal and Spain. Evolving from the single-masted cog, the carrack was first used for European trade from the Mediterranean to the Baltic and quickly found use with the newly found wealth of the trade between Europe and Africa and then the trans-Atlantic trade with the Americas. In their most advanced forms, they were used by the Portuguese for trade between Europe and Asia starting in the late 15th century, before being gradually superseded in the late 16th and early 17th centuries by the galleon.