Duane's take
Here's how the official marker tells it, and I'll do my best to do it justice. Back in 1766, the Viceroy of New Spain had a problem. Rumors were swirling, the kind that keep powerful men up at night, that the English were eyeing Spanish territory along the Texas coast.
Now, when a viceroy gets nervous, somebody gets orders. And the man who got those orders was Diego Ortiz Parrilla. This was not a man you sent on a casual errand.
Parrilla had fought the Moors for Spain before taking on positions of civil and military leadership in the New World. He had a resume. He had a purpose.
And now he had a mission: go find the intruders, and expel them. On September 13, 1766, Parrilla set out from San Juan Bautista on the Rio Grande. What followed was the first expedition to give detailed descriptions of Texas' offshore islands, and the first to refer to Corpus Christi Bay by its present name.
That alone would be enough to put a man in the history books. But the story doesn't stop there. When the party reached Corpus Christi Bay, a detachment broke off and marched south to take a hard look at the coastal islands, right through this very area.
What they found was not exactly encouraging for anybody thinking about moving in. Bleak dunes. No trees.
No water. Just the kind of place that makes even a rumor of occupation seem far-fetched. Their report cast real doubt on whether an enemy could survive out here, let alone establish a foothold.
Then the sky opened up. Torrential rains. Floods.
The kind of weather that doesn't care who sent you or why. Progress slowed to a crawl. But Parrilla pushed on, and at La Bahia, present-day Matagorda Bay, luck paid him a visit.
He was able to interview soldiers who had been serving along the coast, and through those conversations he gathered knowledge of the geography and the Indians stretching as far north as Trinity Bay. Information he never could have mapped on his own. After several months, Parrilla returned.
The rumors of English intrusion? Largely disproved. And tucked inside his report was something the Spanish Crown hadn't expected, a thorough picture of the Texas Gulf Coast, its islands, its bays, its people.
He went looking for an enemy. What he brought back was a map.
What the marker says
First expedition to give detailed descriptions of Texas' offshore islands and to refer to Corpus Christi Bay by its present name. The exploration was ordered by the Viceroy of New Spain in the midst of rumors that the English planned to encroach on Spanish territory. Parrilla, who had fought the Moors for Spain before holding positions of civil and military leadership in the New World, was ordered to expel any intruders. He began his trek at San Juan Bautista on the Rio Grande, September 13, 1766. At Corpus Christi Bay a detachment marched south to explore the coastal islands. Their report of uniformly bleak, treeless, waterless dunes (including this area) cast doubt on the feasibility of enemy occupation. At this point, torrential rains and floods impeded the party's progress. At La Bahia (present Matagorda Bay) Parrilla was luckily able to interview some of the soldiers serving along the coast and thus he obtained knowledge of the geography of the area and its Indians as far north as Trinity Bay. After several months Parrilla returned, having helped disprove rumors of the English intrusion and bearing vital information on the Texas Gulf Coast.