The attackers numbered almost 1,400, including sailors and Indian allies. While the warships blockaded the harbor on the east, William Palmer came in from the north with a company of Highlanders and occupied the deserted outpost called Fort Mose. Oglethorpe landed his men and guns on each side of the inlet and began building batteries across the bay from the Castillo.
Montiano saw at once that all the English positions were separated from each other by water and could not speedily reinforce one another. Fort Mose, at the village of the black runaways a couple of miles north of the Castillo, was the weakest. At dawn on June 26 a sortie from St. Augustine hit Fort Mose, and in the bloodiest action of the siege scattered the Highlanders and burned the palisaded fortification. Colonel Palmer, veteran of Florida campaigns, was among the dead.
As if in revenge, the siege guns at the inlet opened fire. Round shot whistled low over the bay and crashed into fort and town. Bombs from the mortars soared high—deadly dots against the bright summer sky—and fell swiftly to burst with terrific concussion. The townspeople fled, 2,000 of them, some to the woods, others to the covered way where Castillo walls screened them from the shelling.
For 27 nerve-shattering days the British batteries thundered. At the Castillo, newly laid stones in the east parapet scattered under the hits, but the weathered old walls held strong. As one Englishman observed, the native rock “will not splinter but will give way to cannon ball as though you would stick a knife into cheese.” One of the balls shot away a gunner’s leg, but only two men in the Castillo were killed during the bombardment.
The heavy guns of San Marcos and the long 9-pounders of the fast little galliots in the harbor kept the British back. Despite the bluster of the cannonades, the siege had stalemated. Astride the inlet, Oglethorpe and his men battled insects and shifting sand on barren, sun-baked shores, while Spanish soldiers in San Marcos, down to half rations themselves, saw their families and friends starving. On July 6 Montiano wrote, “My greatest anxiety is provisions. If these do not come, there is no doubt that we shall die in the hands of hunger.”
The very next day came news that supplies had reached a harbor down the coast south of Matanzas. Shallow-draft Spanish vessels went down the waterway behind Anastasia Island, fought their way out through Matanzas Inlet and, hugging the coast, went to fetch the provisions. Coming back into Matanzas that same night, they found the British blockade gone; they reached St. Augustine unopposed.
Oglethorpe made ready to assault the Castillo despite the low morale of his men. His naval commander, however, was nervous over the approach of the hurricane season and refused to cooperate. Without support from the warships, Oglethorpe had to withdraw. Daybreak on July 20—38 days since the British had arrived at St. Augustine—revealed that the redcoats were gone.
This 1763 engraving shows the finished Castillo after all the bombproof vaults and a new ravelin had been built.
