In 1860, as the secession crisis began, Hilton Head Island, just as most of the barrier islands from the Chesapeake to the toe of Florida, lacked any military presence. The infrastructure on the island differed little from that depicted on an 1825 map:
Although Port Royal offered good anchorage, the lack of major port facilities diminished its importance to military authorities who had prioritized coastal defense projects. Instead Charleston received the lion’s share of the attention… and funding.
At the start of the war, the Federals needed anchorages in order to maintain the blockade. Thus Port Royal was posted high on the list of objectives. And at the same time the Confederates recognized the vulnerability of Port Royal and fortified Hilton Head and Phillip’s Island across the sound.
In November 1862, Federal actions demonstrated those defenses were not complete, especially against steam powered navies. With Port Royal in Federal hands, Hilton Head became an important base. The island became a sprawling “city” within the span of a year. By mid-war, outposts and fortifications extended out from Hilton Head to protect Port Royal and approaches.
But with the close of the war, the military would not need Port Royal, and thereby Hilton Head would fall back down the list of priorities for post-war coastal defense appropriations. However, military minds had reason to rethink that prioritization given the experience of the Civil War. If the Federals could use Port Royal as a base and lodgement, then a foreign power might also. That in mind, On April 29, 1865, Major-General Quincy Gillmore sent a letter to the Army’s Adjutant-General, Brigadier-General Lorenzo Thomas, in Washington:
General: I have the honor to call your attention to the following statement in relation to the north end of Hilton Head Island, S. C., bordering upon Port Royal Harbor. This, in common with some other portions of the island, has been reserved by the United States Government for military purposes during the war. The fact that it is the headquarters of the department, and its occupation by troops, has drawn thither a large number of sutlers, army followers, and others, until quite a city has grown up. Most of the buildings erected thus far are owned and occupied by the parties above mentioned and have been put up only on condition of their removal at any time when, in the judgment of the military authorities, the interests of the public service demand it. But the impression is gaining ground that after the war this property will no longer be needed for public purposes and that a city will be located here. In my opinion this portion of the island will be required hereafter for permanent fortifications. Therefore, that this may be understood, I desire the authority of the War Department to announce officially that all the lands now reserved at this post for military purposes will be permanently occupied by the Government. Such announcement will remove all grounds for damages in case at any time it should become necessary to require the removal of the buildings. I have the honor to request that this matter may receive your early attention.
Some of the buildings in question were quarters inhabited by former contrabands… a term being discarded in the correspondence with “refugee” or “freedmen.”
Despite Gillmore’s urgings, the War Department would make no significant efforts to maintain or improve the fortifications left behind on Hilton Head. In the decades that followed, one experimental battery was placed on Hilton Head Island. But that was more so to provide trials for new weapons than any scheme of defense. Changes in military technology allowed for different arrangements than that employed during the Civil War. In 1898, construction began on Fort Fremont featuring a battery of 10-inch disappearing guns on Saint Helena Island. Those heavy guns could cover the sound, entrance channel, and Hilton Head with ease. (Earlier in that decade, a coaling station was established on Paris Island. And that post eventually grew into a substantial military presence around Port Royal by the early 20th century.)
But the US Government retained control of significant portions of Hilton Head Island after the Civil War. Some of the pre-war plantation owners returned and reclaimed property. Portions of the lands held by the Government were passed to the freedmen or sold to speculators. But the War Department still held significant holdings on the island as the century closed. And those holdings were used again during World War I and World War II as the military again saw the need to garrison Hilton Head.
However, the most significant change would occur in the decades after World War II. A highway bridge and other improvements transformed the once sparsely populated island where Gullah lived, and occasionally the military garrisoned, into a resort community. In the span of 100 years, Hilton Head went from being a major military base, to a small community living on the margins of the land and society, and then finally to a place of leisure and luxury.
Such is the passing of history.
(Citation from OR, Series I, Volume 47, Part III, Serial 100, page 351.)