The Civilisation of the Ancients
The First Ones. The Lost Tribes. The Ancients. Whatever you call them, they were earliest known inhabitants of what we now call the Sea of Thieves.
Signs of their civilisation can be found all over: cave paintings, potteries, and other artefacts. They built temples, altars — places that were important to them. The Ancients had ships and even a few pirates. There were also artisans and sculptors, philosophers and painters. Their currency was possibly the Ancient Coin, a rare coin emblazoned with what appears to be a skull.
They were an intelligent and creative community, that charted star constellations, told stories, and became aware of the magic that the Sea of Thieves offered. As they mastered the use of magic, they created specially imbued relics such as the 'Shroudbreaker'. They have also been claimed to have used Kraken Ink to see the future, much like how the Order of Souls use Kraken Ink in recent times.
Within their culture, specific titles and roles were given to chosen individuals who lived up to their potential. Such known roles are the Warrior and the High Priest. Some individuals even took on the mantle of sacred animals that were represented in the star constellations.
It is unknown if they were all one united people, or if they lived in different tribes. The monolithic statues found on Tribute Peak at least suggest that there were ten key figures in their society.