"By May 1539, Conquistador Hernando de Soto skirted the coast of Florida, searching for a deep harbor to land. He described seeing a thick wall of red mangroves spread mile after mile, some reaching as high as 70 feet (21 m), with intertwined and elevated roots making landing difficult. Very soon, 'many smokes' appeared 'along the whole coast', billowing against the sky, when the Native ancestors of the Seminole spotted the newcomers and spread the alarm by signal fires". The Spanish introduced Christianity, cattle, horses, sheep, the Spanish language, and more to Florida.[full citation needed] Both the Spanish and French established settlements in Florida, with varying degrees of success. In 1559, Don Tristán de Luna y Arellano established a colony at present-day Pensacola, one of the first European settlements in the continental United States, but it was abandoned by 1561.