Origin of the de Leon Guerrero’s in the Marianas

There are several possibilities for the origin of the compound surname Leon Guerrero.

The matrimonial union between someone with the surname Leon and another with the surname Guerrero could have resulted in a new compound surname which descendants adopted as their sole, hereditary surname.

It could also have been the result of the practice of adding a nickname to a surname of patronymic origin to distinguish it from other families with the same patronymic surname. In this case, Leon could have been the personal name of the original bearer (patronymic) that was taken by his descendent as a surname (son of Leon). A nickname representing the personal attributes of the original bearer is added to further distinguish the family. In this case, Guerrero, from the Castilian word meaning “warrior” signifying “one who was successful in battle.” In the Chamorro culture “Nickname” is referred to “better known as.” In addition to descriptive actions of qualities of the original bearer, nicknames could be based on various references. Some are based on a derivative of a name such as Binu’ derived from the first name “Balvino” (Leon Guerrero) or Teyu which is dervived from the surame “Tello”. A place name could distinguish the nickname such as Manila for the de la Torre family. Objects, animals, food, status, body parts and the full moon are the basis of other family names in the Chamorro “Better-known-as” system.

Another possibility is that Leon is of toponymic origin meaning it is derived from a place that the original bearer lived or held land. Leon is the name of a province and district in Spain.

The surname de Leon Guerrero is found in historical Spanish documents relating to Guam and the Mariana Islands as early as 1717. Interestingly, the “Archivo General Militar de Segovia” does not list the compound surname until 1845 when Luis de Leon Guerrero served in an infantry regiment of the Royal Army of Spain. Only one other soldier is listed with this surname in 1867 when Francisco Leon Guerrero served in the Marines.

Diego de Leon Guerrero was listed as an Ayudante with the First Company of the Royal Camp of San Ignacio de Hagadna [sic] in 1717. Then in 1727 there are 10 individuals with the surname de Leon Guerrero recorded in the list of Spanish residents of Agadna [sic] in the census of the Mariana Islands. The 1758 census lists 47 who carried the surname de Leon Guerrero: 19 from their maternal line and 28 from their paternal line.

According to the last census of the Mariana Islands conducted by the Spanish authorities in 1897 (published in 1898) there were 326 residents bearing the surname de Leon Guerrero: 90 from their maternal line and 236 from their paternal line. There are a number of other entries that are questionable indicating that the number of individuals with the de Leon Guerrero surname could actually be greater.

Over a century (139 years) separates the 1758 census and the 1897 Spanish census. This makes connecting the early de Leon Guerrero family with the current day Leon Guerrero clan problematic. As more historical documentation becomes available to researchers, this gap is expected to narrow and eventually disappear. To further complicate the situation, many individuals changed or modified their surnames when Spanish customs and practices were replaced with American ones after the Spanish American War. Some have been said to completely change their names taking on the surname of their mother or another person while others dropped a portion of their name. For example, de Leon Guerrero became “Leon Guerrero” “DeLeon” or simply “Guerrero.”

Family nicknames are often used in Guam to further distinguish families from the larger clan. The origins of these nicknames can be based on a personal characteristic of the patriarch of the family, a notable event, action, or relationship or simply indicate the matriarch and patriarch of the family (Vicentan Ignacio for a family headed by Vicenta and Ignacio).

The Leon Guerreros of Guam are generally believed to have descended from a common ancestor.