One month after Pearl Harbor, in January 1942, a German U-boat was spotted just miles from the entrance to Aransas Pass. The pass guarded an oil depot and served as the transit route for Port of Corpus Christi vessels — Port Aransas was the nation's 12th largest oil shipping port. The U.S. Army's response was swift: field artillery from the 2nd Infantry Division, followed by Battery E of the 50th Coast Artillery Regiment, equipped with two French-designed 155mm guns mounted on reinforced concrete emplacements atop the sand dunes. A camp was built for 360 men. The guns could reach targets 11 miles out to sea. For two and a half years, they watched the Gulf of Mexico. They never fired a shot.
The Threat
The Southern Defense Command, created in March 1941 under Lieutenant General Walter Krueger, was responsible for the entire Southern U.S. coastline from North Carolina to Brownsville. After Pearl Harbor, the fear of German naval operations in the Gulf of Mexico was not hypothetical — the U-boat sighting near Aransas Pass in January 1942 was real. The oil depot inside the pass and the commercial shipping traffic through the channel made Port Aransas a logical target.
The Response
Key Facts
- Duration
- January 1942 — July 1944
- Personnel
- 360 men
- Primary weapons
- Two 155mm GPF guns
- Range
- 11 miles
- Shots fired at enemy
- Zero
In January 1942, the SDC dispatched a temporary field artillery battery of the 2nd Infantry Division to Mustang Island. They set up 105mm Howitzers as an immediate defensive measure. By April 1942, Battery E of the 50th Coast Artillery Regiment arrived with heavier equipment: two French-designed 155mm GPF (Grande Puissance Filloux) guns.
The guns were mounted on Panama mounts — a type of gun emplacement developed by the U.S. Army in Panama during the 1920s. The troops built reinforced concrete emplacements on top of the sand dunes, along with timber magazines for ammunition storage, a commander's station, and searchlights. The camp accommodated 360 men. The 155mm guns could fire six-inch shells at targets up to 11 miles away.
Two and a Half Years of Watching
Coastal defense operations at Port Aransas lasted from January 1942 to July 1944, when enemy naval threats in the Gulf were assessed as having ceased. During the entire deployment, no weapons were discharged at any enemy. No actual engagements with enemy craft occurred. The guns watched the water, and the water stayed empty.
The military presence had another effect: the population of Port Aransas reportedly doubled during the war years as hundreds of servicemen lived on the island. The town had been small — perhaps 500 people before the war — and the sudden influx of young military personnel changed the social fabric temporarily.
An Older Military History
Mustang Island's military history didn't start with World War II. During the Mexican-American War of 1846 to 1848, a small fort was built on the island to guard the entrance to Aransas Bay and remained in use through the Civil War.
In April 1863, Confederate forces established Fort Semmes on the northern end of Mustang Island — named after Confederate Navy Captain Raphael Semmes. On November 17, 1863, Union forces under Brigadier General Thomas E.G. Ransom attacked Fort Semmes. The Confederate garrison of fewer than 100 men under Major George O. Dunaway was bombarded by the USS Monongahela from offshore. The Confederates surrendered. Union troops occupied the island until July 1864.
And of course, on Christmas Day 1862, Confederate General Magruder ordered the Lydia Ann lighthouse destroyed — an act of military demolition that the lighthouse survived, and that is remembered far better than the fort that stood just up the island.
What Remains
A Texas Historical Commission marker — "World War II Coastal Defenses at the Aransas Pass" (Atlas #5507015267) — documents the wartime installation. Gun mount remnants are still visible in the dunes. Local preservation groups have worked to create a memorial at the site.
The WWII guns that never fired are a quiet story — no combat, no heroics, no casualties. But they represent something important about Port Aransas: even the military history of this island is defined by the tension between preparation and the Gulf's indifference. The guns waited. The threat never came. And then the men went home.