The Rules That Governed the Sea
The sea has always been governed by law. From the ancient Rhodian Sea Law (800 BCE) to the papal bulls that legalised slavery, to the modern Law of the Sea — maritime law shaped who could sail, who could trade, and who could be enslaved. Understanding these laws is essential to understanding how the Cape Verde founder event — and your ancestry — came to be.
The oldest known maritime law code is the Lex Rhodia — the Rhodian Sea Law — developed on the island of Rhodes around 800 BCE. It established principles that still govern maritime law today: the law of general average (if cargo must be thrown overboard to save the ship, all merchants share the loss proportionally), the rights of sailors, and the rules of salvage.
The Romans adopted the Rhodian Sea Law wholesale. Justinian's Digest (533 CE) records: 'The Rhodian law provides that if merchandise is thrown overboard for the purpose of lightening a ship, the loss incurred on behalf of all shall be made up by the contribution of all.' This principle — that the community shares both the risks and the benefits of the voyage — is one of the oldest legal concepts in the world.
The sea has always required cooperation. No single person can sail a ship alone. Maritime law is the codification of that necessity — the rules that make collective voyages possible.
In 1452, Pope Nicholas V issued the papal bull Dum Diversas, granting Portugal the right to 'invade, search out, capture, vanquish, and subdue all Saracens and pagans whatsoever, and other enemies of Christ wheresoever placed, and the kingdoms, dukedoms, principalities, dominions, possessions, and all movable and immovable goods whatsoever held and possessed by them and to reduce their persons to perpetual slavery.'
In 1455, the bull Romanus Pontifex extended this to all people south of Cape Bojador on the West African coast. This papal bull — issued from the Arquivo Nacional da Torre do Tombo in Lisbon — legally created the Atlantic slave trade. It is the legal foundation of the Cape Verde founder event that created your genome.
The same legal system that created the slave trade also created the founder population of Cape Verde — and therefore you. Understanding this her story is not optional. It is the foundation of knowing who you are.
Cape Verde was uninhabited when the Portuguese arrived in 1462. The islands were settled under the authority of the papal bulls — Portuguese colonists (carrying Germanic, Scandinavian, Iberian, Celtic, and Mediterranean ancestry) were granted land, and enslaved West Africans from Senegambia were brought to work it.
The founder population was small — perhaps 50-200 Portuguese colonists initially, mixed with West African populations from Senegambia, Guinea-Bissau, and the Gambia. The founder effect amplified this diversity in all subsequent generations. Ten ethnicities in one genome is the mathematically predictable result of this small founding population.
Your great-grandparents were among those who crossed from Spain/Portugal to Cabo Verde in 1492 — the same year Columbus sailed west. The same maritime law that sent Columbus west also sent your ancestors south.
The United Nations Convention on the Law of the Sea (UNCLOS), signed in 1982, is the modern successor to the Rhodian Sea Law. It defines the rights and responsibilities of nations with respect to their use of the world's oceans — establishing guidelines for businesses, the environment, and the management of marine natural resources.
Key principles of UNCLOS: the territorial sea (12 nautical miles from shore), the exclusive economic zone (200 nautical miles), the freedom of the high seas, and the right of innocent passage. These are the rules that govern the same waters your ancestors crossed.
From the Rhodian Sea Law of 800 BCE to UNCLOS of 1982 — 2,800 years of maritime law. The sea has always been governed. The question is always: governed for whose benefit?