In 1766, Diego Ortiz Parrilla led the first expedition to give detailed descriptions of Texas' offshore islands and to refer to Corpus Christi Bay by its present name. Ordered by the viceroy of New Spain amid rumors that the English planned to encroach on Spanish territory, Parrilla, who had fought the Moors for Spain before holding civil and military leadership posts in the New World, was sent to expel any intruders. He began his trek at San Juan Bautista on the Rio Grande on September 13, 1766. At Corpus Christi Bay, a detachment marched south to explore the coastal islands, and its report of uniformly bleak, treeless, waterless dunes, including this area, cast doubt on the feasibility of enemy occupation. Torrential rains and floods then impeded the party's progress. At La Bahia, present Matagorda Bay, Parrilla was able to interview some of the soldiers serving along the coast and obtained knowledge of the geography of the area and its Indians as far north as Trinity Bay. After several months he returned, having helped disprove rumors of English intrusion and carrying vital information on the Texas Gulf Coast.