These forces arrived in time to deal with the only serious invasion of Spanish Florida. James Oglethorpe fancied himself a general in addition to colonial master, and when it was clear the war was imminent he began to muster his forces. In theory the Cherokee, Uchee, Creek, Georgia, and South Carolina were supposed to be providing men for the campaign, but there were the usual excuses that came with any group project. The Cherokee were only there with about 200 men, and their troops kept wandering off or getting distracted. The Creek were sick, the Yuchi were just along to raid Spanish Florida for pocket change, and South Carolina sent a whole ten Scottish rangers and expected to take charge anyways. Even so, Oglethorpe eventually got a force of about 900 colonial and British troops together and 1,100 indigenous allies.
For a comparatively small force, problems abounded. The command structure of the British force was a flow chart nightmare. Oglethorpe held overall command, but he ceded day to day operations to a South Carolina militia man named William Palmer. Palmer in turn could only make “suggestions” to the regular British troops, and the Georgians resented serving under a South Carolinian. Their leader Captain Mackay in turn hated Palmer, and as a Scottish regular had his own opinions about taking orders from some colonial hick with an inflated ego. Oglethorpe also turned out to be a stickler for things like insisting the Native American troops fight by lining up European style rather than sensibly taking cover.
The situation did not improve when they actually reached the outskirts of St. Augustine in May 1740. Unlike the British, Spanish Governor Manuel de Montiano actually had firm command of his own mix of Spanish regulars, free black militiamen, and Yamassee. The British might as well have announced their arrival with trumpets, as the wave of Uchee and Creek raids had pretty much signaled the arrival of a besieging army. Montiano took his time and carefully dug in around the town, situated on the Matanzas River. Talking it over, he and the late arriving British Commodore Vincent Pearse decided to starve out St. Augustine and encircled the town from sea. On land, Palmer settled his vanguard at the now evacuated Fort Mose, close enough to the main town to ambush any foraging parties in a loose siege. To keep the Spanish on their toes the navy began shelling the fortifications around town.
Most sieges end this way. The defenders, bottled up inside with no hope of relief, were demoralized and miserable. On a regular basis, Oglethorpe’s men would parade around in sight of St. Augustine, just to reinforce the point. But de Montiano was not one to sit idle and wait for the end, and he bided his time for a chance to strike. The cracks in the British command structure had only grown, and the effects were trickling down to the rank and file. Palmer and Mackay were no longer on speaking terms, and one of their worst disputes meant a portion of the siege line had no sentries on it. The Colonel had resorted to calling “surprise” drills at three in the morning, then shouting at the men every dawn for being too slow or too lazy to respond, which had only poured gasoline on the men’s burning resentment. Everyone also hated Oglethorpe for the ceaseless, pointless marching. In late June, everything came to a head when de Montiano attacked fort Mose.
About a hundred and fifty British highlanders, Creek and others were camped around the fort, and they were caught completely offguard. As it happened, Colonel Palmer had known what he was about, even if expressing it in his shouty, obnoxious way had come at a high cost. The Spanish hit the fort in the early hours of the morning and easily forced their way inside. After a short sharp fight Colonel Palmer was shot reloading his musket and died. Mackay tried to hold the troops together dressed in his underwear and a nightshirt but had to run for it as the Spanish overwhelmed the line. By morning the British position was gone, and morale plummeted among the besiegers. For the cost of maybe ten men, de Montiano had inflicted maybe 90 casualties on the enemy. Awkwardly, Oglethorpe demanded the Spanish surrender just four days later, which went over about as well as expected. For another month Oglethorpe kept up the siege, but there was no point to it. The sally cracked the siege line, and morale sank among the besiegers. By July Commodore Pearse’s concern for hurricane season left the blockading force too far out to sea, and a Spanish flotilla snuck in to resupply the garrison. With the siege a clear failure, Oglethorpe and the other components of the invasion force slunk home and began to immediately work at shifting the blame around. For later historians, sifting through accounts of the siege means relying on biased accounts like the Georgian Thomas Jones, who blamed,
“I wrote to you from Fort Diego in Florida July 6th ultimo wherein I gave you some account of the state of our then warlike preparations against the Spaniards, which have not succeeded according to expectation. Many of the Carolina officers ran away, several of the private men both of the Carolina and of the General’s own regiment (being Irish) deserted and went to the Spaniards. The flux and fever raged, especially among the Indians in the camp. The captains of our men of war before Augustine were not unanimous and at length quitted that station, fearing the hurricanes which sometimes have happened in the months of August or September in these coast.”
The South Carolinians in turn blamed Oglethorpe, and called him to account for his failure in Charleston. Regardless of how it happened, the invasion of Spanish Florida was a first rate debacle, and the front in North America ceased to be a focal point of the war for the year.
 This is the 18th Century, so joking aside this meant a horrific bout of smallpox was sweeping through the Creek Nation.
 Mills Lane (ed.), General Oglethorpe’s Georgia: Colonial Letters, 1733-1743 (Savannah: Beehive Press, 1990), Vol. II, p. 474.