The Puerto Rican Campaign (also: San Juan Campaign) refers to American operations on the island of Puerto Rico in the final stages of the Spanish-American War.

Left unfinished by the announcement of the armistice on August 13, the battle for Puerto Rico is generally regarded as an American victory, though Spanish opposition along the island's fortified northwest had stiffened considerably and may indeed have proven fierce.

Initial Landings

Nelson Miles shocked both American and Spanish military authorities when, in defiance of orders from President McKinley, who had approved a highly publicized amphibious siege of the heavily fortified capital of San Juan, he opted instead to land his forces on the very opposite corner of the island, at the southwest port of Guanica.

Criticism of this daring move, however merited, was quickly silence by its strategic brilliance. Western Cuba, a region of largely pro-American populace, had been only lightly garrisoned by the Spaniards, who had concentrated their defenses in the vicinity of San Juan. In the face of a massive and unexpected invasion from the rear, Spanish forces lost coherence, mounting disjointed and uncoordinated resistance, or withdrawing to the northeast without giving battle.

Moreover, many cities rejoiced at the prospect of a change in government and willfully surrendered to American forces.

Battle of Yacau

At the Battle of Yacau, July 26, 1898, three Spanish companies under Colonel Puig attempted to halt the advance of General Garretson's army in the darkness of the early morning. Repulsed by American counterattacks at dawn, Puig turned and retreated his forces far to the north.

Garretson, discovering that his reserves had deserted overnight, nevertheless maintained a vigorous pursuit, opening most of southwestern Puerto Rico to American control.

Battle of Guayama

The Battle of Guayama signaled the successful American capture of Guayama, Puerto Rico, located a few miles north of a large American landing site at Arroyo.

Approaching the town, the American force had come under sniper fire from small parties of Spaniards, but had maintained its advance. Lacking the manpower and supplies necessary to hold their positions before such an overwhelming force, the Spanish retreated out of the city before the American arrival.

Battle of Guamani

Following the capture of Guayama, the northwestern advance of Hain's brigade was on August 9 again contested at the Battle of Guamani.

Nearing the Guamani River, the American vanguard came under fire from elements of Spain's 6th Provisional Battalion. A short firefight erupted, in which American numerical superiority forced the Spanish back across the Guamani River Bridge.

The American advance through Puerto Rico continued.

Battle of Coamo

The Battle of Coamo, which followed a short siege of the town, was an American effort to encircle and destroy the Spanish garrison at Coamo, Puerto Rico, one of the last Spanish bastions south of San Juan.

While his artillery battered and distracted Spanish defenses, General Wilson had infiltrated the 16th Pennsylvania Volunteers around the far side of the city, hoping to trap the Spanish and submit them to a crossfire.

The Pennsylvania's rear assault was then rapidly reinforced by the bulk of Wilson's army under General Ernst, whose charge closed the pincer on the Spanish defenders.

American attempts to pursue Spanish elements retreating north to San Juan were abandoned in the face of heavy fire at Abonito Pass.

Battle of Silva Heights

The Battle of Silva Heights was fought during Theodore Schwan's drive up the west coast of Puerto Rico.

A considerable force of Spanish regulars and auxiliaries, encamped on the high ridge overlooking Hormigueros, struck Schwan's Brigade on August 10, hoping to turn it back. Initially, the attack was successful, pinning the 5th cavalry in place and preventing the 19th infantry from reinforcing American positions.

The Spanish lacked artillery support, however, and could not answer Shwan's gatling guns and large-caliber cannons. As Schwan's Brigade pressed forward, surging along the ridge's flank, Spanish numerical inferiority began to tell. Outgunned, Colonel Villanueva ceded the heights to the enemy and withdrew his men east to Lares.

Battle of Abonito Pass

The Battle of Abonito Pass, the last battle of the Puerto Rican Campaign, was in fact interrupted by news of the August 13 armistice before its outcome could be decided.

On August 12, Generals Wilson and Ernst had deployed two brigades along the Spanish defenses between Barranquitas and Cayey, chief of which were the guns at Abonito Pass. Following several successful reconnaissance missions to determine enemy strengths and positions, General Wilson ordered an offensive along the Spanish flank accompanied by heavy artillery bombardment. Met with fierce Spanish resistance and defensive artillery fire, the American attacks collapsed, and Wilson settled the troops for the evening.

Early next morning, before renewed assaults could begin, American commanders received telegraphs informing them of the armistice. The battle for Puerto Rico was over.

Aftermath

Under the terms of the Treaty of Paris, Puerto Rico was annexed by the United States as a self-governing commonwealth.