In 1763 the British gained control of both East and West Florida, with West Florida extending to the Mississippi River. Most of the Floridano Spanish military and their families moved to Cuba or other Spanish colonies; however, Ruiz del Canto was appointed by the Spanish government as one of the eight persons left in charge of the real estate in St. Augustine. 

He made many trips to Florida with his job, and he not only looked after Spanish interests, but also interpreted and negotiated with the Yuchi Indians. Resentment from the Colonists continued to build toward Britain and the British were encroaching on Spanish Louisiana territory. As the Governor and military leader of Spanish Louisiana territory, General Bernardo de Galvez needed intelligence regarding the British defenses in West Florida and assessments on the Native tribes’ alliances. A Spanish network of spies was created and Ruiz del Canto volunteered. He was tasked to convince both the Native tribes to stay neutral like the Yuchi and to find out about the British military capabilities in West Florida.

In 1779, the Spanish declared war on Britain, thereby creating an alliance with the Colonists. In February 1780, on a trip to Louisiana to brief General de Galvez, Ruiz del Canto captured a small British schooner and a British Captain. The prisoner was then taken to Spanish Cuba where he was interrogated and during his interrogation, he gave strategic information about British troop locations and their naval presence in Pensacola. This information was crucial for General de Galvez’s planning of the March 9, 1781 Siege of Pensacola. When the Spanish regained West Florida, they granted the Americans access to the Mississippi River. This benefited the Colonists greatly in their fight for Independence.