Guam Family History Research is complicated by the island's history. This spans ancient Chamorro (ingenious native) settlement through to Spanish, Japanese and eventually American control. Located in the western Pacific Ocean it's the most southern of the Mariana group of Islands, the remaining fourteen of the group forming The Commonwealth of the Northern Mariana Islands (CNMI).
As in the case of the CNMI and other U.S. Unincorporated Territories (Puerto Rico, U.S. Virgin Islands and American Samoa) researching Guamanian family history can be particularly challenging. Some records are lost, others are inaccessible, have been destroyed or may reside in the archives of its former long-term colonial power, Spain. This article aims to assist the family historian with information, strategies and sources with their genealogical research in Guam. A separate overview article on How To Research Family History In United States Unincorporated Territories provides further, more generalised guidance.
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History of GuamHistory of Guam
Chamorro people, originating from Southeast Asia around 4,000 years ago, settled Guam around 1500 BCE. As in other Marianas islands the Chamorro in Guam developed a distinct architecture. This is known as latte, for the use of conic, ancient stone pillars capped with hemispherical stones (tasa). Latte served as foundations for significant Chamorro buildings and became an important symbol of their identity, society and culture[1].
The explorer Ferdinand Magellan arrived in Guam in 1521 and in the following decades it became a key provisioning stopover for sea trade between the Spanish ports in the Phillipines and Mexico. The first permanent Spanish settlement in Guam was established in 1668. Over the next 230 years Spain transformed the island from a traditional Chamorro society into a key strategic outpost for the Spanish Empire. This era was defined by the increasing influence of the Catholic Church, the Spanish-Chamorro Wars and Spain's Reducción policy, which forced the indigenous population into church-dominated villages. Over the centuries of Spanish rule conflict and introduced European diseases decimated the Chamorro people, estimated to have been reduced in number by nearly 90%[2].
The United States captured Guam bloodlessly in 1898 during the Spanish-American War and it was permanently ceded to the US by the Treaty of Paris in 1898. U.S. Navy governors ruled from 1899, building infrastructure but also imposing martial law and limiting Chamorro rights. Japan seized Guam hours after the attack on Pearl Harbor in December 1941. Japanese occupation continued until U.S. forces recaptured Guam in July 1944 after heavy fighting, with the Chamorro also badly affected.
The 1950 Organic Act established a civilian government in Guam and granted Guamanians U.S. citizenship. A later (1968) Act established the post of locally elected Governor. Guam remains an unincorporated U.S. territory with a non-voting representative in Congress. Guamanians cannot vote in U.S. presidential elections[3].
Popular surnames in the Guam and their accepted meaningsPopular surnames in the Guam and their accepted meanings
Common surnames in Guam reflect heavy Spanish colonial influence and share many similarities with those in neighbouring Northern Mariana Islands (CNMI). The main difference is the frequency or prominence of particular surnames. CNMI surnames also incorporate the traditions and impact of migrants from the central Caroline Islands of Micronesia that occurred in the 19th century and who eventually merged with the indigenous Chamorros[4].
Traditionally Chamorros used single names or clan descriptors without fixed surnames. The Spanish term familia in Chamorro culture refers to an extended clan, not just immediate family, based on common ancestors. These names often described physical traits, status or actions. They were used to creating distinct branches (Ramas) within a Familia[5]. Examples of Guamanian surnames of Chamorro origin include:
- Taitano: "No Land" or "Landless."
- Aguon: "Sustenance," "Bread," or "Basic Food" (specifically taro or starch).
- Chargualaf: Believed to be derived from the combination of the Chamorro words "cha'gu" meaning "to be strong" and "laf" meaning "to be brave."
- Quinata: Etymology is debated.
- Gogue: Etymology is debated. May be a Chamorro version of an English surname.
- Taijeron: Etymology is debated.
Many Chamorros, either by choice or practicality adopted the surnames of Spanish soldiers, priests, or officials during the 300+ years of Spanish rule. Spanish-style surnames were mandated by the introduction of baptismal registers in the 17th century. Most of these surnames derive from Spanish patronymics, places, or nicknames which were blended into Chamorro identity. Popular Spanish-origin surnames on Guam include:
- Cruz: "Cross." The most common surname on Guam.
- Santos: "Saints" or "Holy."
- Leon Guerrero: "Lion Warrior." A distinct "compound surname" which is highly regarded on Guam. While Leon and Guerrero exist separately, the combined Leon Guerrero is treated as a single dynastic family name.
- Duenas (Dueñas): Habitational name from Dueñas, a place in Palencia, named from the plural of dueña ‘nun’ (from Latin domina).
- Flores: "Flowers."
- San Nicolas: "Saint Nicholas."
- Camacho: "Twisted", "Disfigured", "Weak" (archaic Spanish meaning).
There are also surnames of Filipino origin, reflecting Guam's long-standing connections to the Philippines from centuries of Spanish sea trade. Examples include:
- Pangelinan: One of the most prominent "Chamorro-Filipino" blended families.
- Baza: Origin unclear. Likely of Italian/Spanish origin via the Philippines. May be habitational name from the town of Baza in Granada, Spain.
Spanish forms still dominate 80%+ of all surnames Guam. However more recent American rule in Guam has influenced surnames by formalising and altering Spanish conventions, moving from the Spanish tradition of two surnames (father's then mother's) to the American single surname (father's) order, standardising spellings and encouraging modern practices such as the inclusion of middle names[6]. Examples of common surnames on Guam of American/English origin include the following:
The Guampedia website (see below for details) can offer further details on specific family histories and migration patterns associated with these names.
Some prominent Guamanians or people associated with GuamSome prominent Guamanians or people associated with Guam
Politics and governmentPolitics and government
- Lou Leon Guerrero: Current Governor of Guam (as at 2026), first female governor. Physician by training.
- Robert A. Underwood: Former U.S. House Delegate for Guam (1993–2003), educator and University of Guam president.
- Eddie Baza Calvo: Former Governor (2011–2019), businessman and Republican leader.
- Antonio Borja Won Pat: First Delegate from Guam to U.S. Congress (1973–1985).
SportsSports
- Jon Tuck: Mixed Martial Arts fighter, first Chamorro signed to UFC.
- Derek Mandel: Track and field athlete.
- Benjamin Schulte: Triathlete and swimmer, represented Guam in the 2012 and 2016 Olympics.
- Ray Robson: Chess grandmaster; at 14 the youngest ever U.S. grandmaster.
Entertainment and artsEntertainment and arts
- Pia Mia (Pia Mia Perez): Singer-songwriter and actress.
- Ann Curry: Emmy-winning journalist and former *Today* show co-anchor.
- Q. Allan Brocka: Filmmaker and director.
See AlsoSee Also
- United States
- United States family history records
- US National Archives
- United States Census: State And Territorial Census Records
- How To Research Family History In United States Unincorporated Territories
- Northern Mariana Islands Family History Research
- Spain Historical Records
- Spanish Empire
- Chamorro Surnames
- Hispanic Surnames
Explore more about Guam family history researchExplore more about Guam family history research
Researching family history in Guam usually requires combining local records with more general U.S. territorial (including naval) sources. Given the dominance of the Catholic Church during the period of Spanish colonial rule church records are especially vital for tracing ancestors who lived during those times. The first step is to collate and record as much information as possible about names and locations associated with persons of interest. This will help you match people in fragmented records and navigate surname shifts that may have occurred over time or as the result of colonisation. If possible try to identify the Clan Name of the person being researched (via Guampedia--see below--or family elders) to identify their specific branch of common surnames.
For general research on Guam you can start with MyHeritage, which offers around almost 15 million U.S. records spread across around 3,600 individual collections. MyHeritage has the full set of USA census records from 1790 to 1950, with a total of 650 million names. These records constitute the single most important source of documentation for family history in the USA. For family research on the American-period of Guam the 1920, 1930, 1940 U.S. Census records are on particular value.
For more specific Guamanians records and information sources here are some online guides and indexes to consult:
- The Chamorro Roots Genealogy Project: A comprehensive database which is a good starting point for Chamorro ancestry research. It includes records from the 1897, 1920, and 1930 Censuses (fully transcribed) and connects individual surnames to their "Clan Names". A paid subscription is required for full access but indexes are free.
- Guampedia: The official online encyclopedia of Guam. Helpful in understanding "Clan Names". It also lists historical figures and village histories which provide context for family origins.
Deeper research on Guam family history may require a visit to the island or hiring an expert genealogist as it typically involves inspection of physical records, not available online.
- Micronesian Area Research Center (MARC) at the University of Guam, Mangilao, holds the Jane Underwood Genealogy Cards. This is a massive physical index of families created by anthropologist Jane Underwood. It is one of the most valuable genealogical tools on the island. The Center also holds Spanish-era documents, land records, and baptismal records pre-WWII.
- The Nieves M. Flores Memorial Library, at the Hagåtña Public Library (also known as the Guam Collection or the Guam Room), houses obituary archives, village yearbooks, and old newspapers (like the Guam Recorder) which can be valuable in confirming death dates and identifying related family members[7].
- Since the vast majority of Guam's history is tied to the Catholic Church, baptismal and marriage records are another potential resource for the family historian. The Archdiocese of Agana Archives holds baptismal, confirmation and marriage registers. As at January 2026 the Archives were temporarily unavailable while they were being physically re-located. These certificates are only issued to the person whose record it is, or to a person who provides proof of parental authority, guardianship, power of attorney, executor/personal representative or other legal status on behalf of the person whose record is requested, and clergy, parish, or Archdiocesan personnel in need of records for official purposes.
- Some village parishes (like those in Inarajan or Merizo) maintain their own older sacramental records. Note however that many pre-WWII records were lost during the 1944 bombardment of Guam. The Catholic Directory: Guam lists contact details for each of the parishes.
References
- ↑ Pereda, N. (2025b, October 16). Latte. Guampedia.
- ↑ Pereda, N. (2025a, August 22). Spanish response to Chamoru/Chamorro depopulation. Guampedia.
- ↑ Wikimedia Foundation. (2025, November 21). History of Guam. Wikipedia.
- ↑ Wikimedia Foundation. (2026, January 2). Carolinian people. Wikipedia.
- ↑ Pereda, N. (2025c, December 5). Chamoru/Chamorro surnames. Guampedia.
- ↑ Jolene Toves | The Guam Daily Post. (2025, February 18). What’s in a name? genealogy workshop explores evolution of Chamoru choices. The Guam Daily Post.
- ↑ Pereda, N. (2025d, December 10). Nieves M. Flores. Guampedia.