In 1667, Spain formally claimed them, established a regular colony there and in 1668 gave the islands the official title of "Las Marianas", in honor of Spanish Queen Mariana of Austria, widow of King Philip IV of Spain and Queen Regent of the Spanish Empire ruling during the minority of her son King Charles II. They then had a population of more than 50,000 inhabitants. With the arrival of passengers and settlers aboard the Manila Galleons from the Americas, new diseases were introduced in the islands, which caused many deaths in the native Chamorro population. The native population, who referred to themselves as "Taotao Tano" (people of the land) but were known to the early Spanish colonists as "Chamurres" or "HachaMori", eventually died out as a distinct people, though their descendants intermarried. At the Spanish occupation in 1668, the Chamorros were estimated at 50,000, but a century later only 1,800 natives remained, as the majority of the population was of mixed Spanish-Chamorro blood or mestizo. They were characteristic Micronesians, with a considerable civilization. In the island of Tinian are some remarkable remains attributed to them, consisting of two rows of massive square stone columns, about broad and high, with heavy-round capitals called latte stones. According to early Spanish accounts cinerary urns were found embedded in the capitals.