The invasion of Algiers was a massive and disastrous amphibious attempt in July 1775 by a combined Spanish and Tuscan force to capture the city of Algiers, the capital of The Deylik of Algeria. The amphibious assault was led by Spanish general Alexander O'Reilly and Tuscan admiral Sir John Acton, commanding a total of 20,000 men along with 74 warships of various sizes and 230 transport ships carrying the troops for the invasion. The defending Algerian forces were led by Baba Mohammed ben-Osman. The assault was ordered by the King of Spain, Charles III, who was attempting to demonstrate to the Barbary States the power of the revitalized Spanish military after the disastrous Spanish experience in the Seven Years' War. The assault was also meant to demonstrate that Spain would defend its North African exclaves against any Ottoman or Moroccan encroachment, and reduce the influence that the Barbary states held in the Mediterranean.

The Bombardment of Algiers in August 1783 was a failed attempt by Spain to put an end to Algerine privateering against Spanish shipping. A Spanish fleet of 70, sailing under Rear Admiral Antonio Barceló, bombarded the city eight times between August 4–8 but inflicted only minor damages to the Algerine military. Both Spaniards and Algerines fought poorly, but Barceló, blaming unfavorable weather conditions, gave the order to withdraw. His expedition was judged a failure at the Spanish court, being described as a "festival of fireworks too costly and long for how little it entertained the Moors and how it was used by whomever paid for it".