The Russian Imperial Alejandro (Spanish for Imperial Alexander) Regiment is a quite unknown unit. It was made up from spaniards from the Joseph Napoleon Regiment who defected en masse to the Russian lines. Actually, when the spaniards made their move, both French and Russian forces first thought the spaniards were charging the enemy!
The Spanish-Russian regiment thus formed was appointed as a personal guard to the Empress Mother in Saint Petesburg and did not see any further action in Russia. One year later, it sailed back to Spain and joined the regular Spanish army, where they were known as el Regimiento Moscovita, the Muscovite Regiment.