Capturing the bay from the Spanish forces was instrumental in the following Battle of Santiago de Cuba and the subsequent invasion of Puerto Rico.

Soon after the rebellion began, two insurgent leaders – José Martí and General Máximo Gómez – had landed at the beach of Cajobabo, between Guantánamo Bay and Cape Maisí, but after three years of fighting throughout the island, the rebels had only been successful in two provinces – Oriente and Camagüey.

[citation needed] Following the explosion of the battleship USS Maine in Havana harbor in February 1898, the U.S. declared war on Spain in support of the Cuban insurgents.

The Spanish gunboat Sandoval was based at Caimanera on the inner bay, and a string of blockhouses defended the railroad to Guantánamo City, 14 mi (23 km) inland.

Commander McCalla had been detached by Admiral Sampson from the blockading fleet at Santiago and ordered to reconnoiter the bay for a naval base.

Upon returning to the blockading fleet from the reconnaissance, Marblehead carried two Cuban officers who had been brought off to the ship from Leeward Point (the western side) of Guantánamo Bay.

Lieutenant Rowan in the famous "A Message to Garcia") to report that the Cuban forces, whose outposts occupied positions on the coast from the mouth of the Yateras to a point 15 mi (24 km) west of Santiago were at the disposition of the U.S. Commander-in-Chief.

[3] Lt. Col. Huntington sought assistance from Commander McCalla, who ordered Reiter to release the Marines' ammunition at once: "Sir, break out immediately and land with the crew of Panther, 50,000 rounds of 6-mm.

With the sea at their backs, a lack of mutual support between outposts, and the thorny scrub and cacti of the arid hills stretching in a dense tangle before them, the Marines had a less-than-ideal tactical position.

Spanish forces defending the area were desperately short of food, and delayed attacking until the Marines had completed unloading their stores in hopes of seizing the American supplies.

Lt. Col. Huntington was joined in the afternoon by Colonel Laborde of the Cuban army, who for several days had been with Commander McCalla as pilot on Marblehead, and now had been sent ashore to assist the Marines and provide intelligence about the enemy.

[3] This occupying force of about 500 soldiers and guerrillas, joined by the troops driven from the blockhouse on the bay, constituted the gravest threat to the U.S. base of operations.

At Camp McCalla, the Marines dug in and began firing at the concealed Spaniards, aided by three 3-inch field pieces and two additional 6 mm Colt–Browning machine guns which had been landed on 12 June by the USS Texas.

[4] Familiar with guerrilla tactics, the Cuban insurgents deployed in pairs in front of the camp, burning the brush and undergrowth as they advanced, thus denying to the enemy of cover.

[4] It was almost 11:00 when the main force reached the steep, horseshoe-shaped hill around Cuzco valley; the commanders of Companies C and D rejoined their units fifteen minutes later.

The smaller Marine force approached on the double, using their 6 mm (0.236-inch) Lee rifles to pour a deadly crossfire on the enemy flank.

[15] During this portion of the fighting, Captain Elliott had requested that Dolphin provide fire support to the Marines by shelling the Spanish blockhouse and nearby positions with her naval guns.

Through a miscommunication of signals, however, the gunboat began unknowingly dropping shells in the direct path of a small force of fifty marines and ten Cuban irregulars led by 2nd Lt. Magill, who was attempting to flank the Spanish position and potentially cut off any avenue of retreat.

[4] Affixing his handkerchief to a long stick and braving the Spanish fire, Sergeant John H. Quick took up an exposed position on the ridge to immediately wigwag a flag signal to Dolphin to adjust her gunfire.

If the young sergeant had had the smallpox, the cholera, and the yellow fever, we could not have slid out with more celerity.As men have said often, it seemed as if there was in this war a God of Battles who held His mighty hand before the Americans.

To deliberately stand up and turn your back to a battle and hear immediate evidences of the boundless enthusiasm with which a large company of the enemy shoot at you from an adjacent thicket is, to my mind at least, a very great feat.

One need not dwell upon the detail of keeping the mind carefully upon a slow spelling of an important code message.I saw Quick betray only one sign of emotion.

[4] The Spanish headquarters building (blockhouse) was burned, and the freshwater well at Cuzco was destroyed, thus ending its immediate usefulness, including to the Marines, whose officers would not let them drink from it prior to its destruction.

Apparently expecting the U.S. forces to follow up the victory, they fortified Dos Caminos, a small settlement at the crossing of two roads, and added several blockhouses to the number already erected on the rail line.

It was determined to rout the last enemy force remaining in the vicinity of the bay, and on 25 June Lt. Col. Huntington led two companies of Marines and 40 Cubans in an amphibious assault on Hicacal Beach.

An American expeditionary force of 17,000 officers and men under Major General William R. Shafter was landed east of the city at the small ports of Daiquirí and Siboney between 22 and 25 June, without opposition.

A week later, on 1 July, the historic battles of El Caney and San Juan Hill ended in victory for U.S. forces, opening up the approaches to Santiago itself.

After the Navy cut the cables and established a base at Guantánamo Bay, General Pareja remained in complete ignorance concerning the course of the war because the Cuban insurgents maintained such a tight ring about the city that not one messenger got through their lines.

Naval forces and a battalion of Marines at Guantánamo Bay, plus the stranglehold on land communications by 1,000 Cuban insurgents, effectively pinned down an army of 7,000 men which might have changed the outcome of the fighting at Santiago.

Less than a week after the surrender of Santiago, the base at Guantánamo Bay was used to launch the invasion of Puerto Rico, 500 mi (800 km) to the east.