In April 1805, as a midshipman, he sailed on the Argonauta, flagship (and sister ship of the Neptuno) of the Commander-in-Chief of the Spanish Navy, Gravina, as part of the squadron headed for Martinique.

[3] In October 1808, as a lieutenant colonel, Porlier commanded the 1st Regiment of Provincial Grenadiers, belonging to General Galluzo's Army of Extremadura.

However, on learning the following day that Soult had defeated Blake at Espinosa de los Monteros they now found themselves in unknown territory and separated from other Spanish troops.

On 10 March, they attacked the French battalion garrisoned at Aguilar de Campóo, capturing nine officers, 400 soldiers and two 4-pounder guns, which were taken to Oviedo and handed over to the Junta del Principado.

[3] Crossing over into France, his troops saw action there until the beginning of December, when they returned to Spain and Porlier's division was garrisoned at Bilbao[3] for the rest of the war.