Fort Manhassett was located six miles west of Sabine Pass near State Highway 87 in southeastern Jefferson County. After the battle of Sabine Pass Confederate authorities feared that another Union invasion force might strike the upper Texas Gulf Coast near Sabine Pass. To block this threat, a series of five earthen redoubts was built on the ridges west of the city, thus preventing either a Union attack on the rear of Fort Griffin or a flanking movement aimed at Beaumont. The defenses were named Fort Manhassett after the Union coal schooner Manhassett, which was beached nearby during a storm on September 29, 1863. Seven companies, commanded by Maj. Felix McReynolds, held Fort Manhassett in October 1863; the force had been reduced to 266 men by January 1, 1864. As late as March 1865 the post still had six heavy guns and two field pieces. Forts Griffin and Manhassett were both abandoned shortly before May 24. Excavations at the latter reveal that the Confederates buried their shells and gunpowder before the evacuation. A plaque now marks the location of the abandoned fort.