Chamorro refers to the indigenous people of the Mariana Islands, a chain of 15 islands in the western Pacific that includes Guam and the Commonwealth of the Northern Mariana Islands (CNMI). The term also describes their language and culture. With roots stretching back roughly 3,500 to 4,000 years, the Chamorro are among the earliest peoples to have settled the remote Pacific islands.
Origins and Migration
The ancestors of the Chamorro people migrated eastward from Island Southeast Asia, likely from the area around modern-day Sulawesi and the Moluccas in Indonesia. Archaeological evidence places their arrival in the Marianas around 3,600 years ago, marked by the appearance of a distinctive red-slipped pottery known as Marianas Red. Genetic research published in the American Journal of Human Biology suggests the founding population was small and developed unique genetic mutations in relative isolation over thousands of years.
A second wave of migration from Southeast Asia may have arrived around 1,000 years ago, bringing with it rice agriculture and the construction of latte stone pillars, tall limestone columns that supported raised buildings and became one of the most recognizable symbols of Chamorro heritage. Both genetic and archaeological evidence point to ties with Indonesia for this later wave.
The Chamorro Language
Chamorro is an Austronesian language, placing it in the same vast language family as Tagalog, Malay, and Hawaiian. But unlike the languages of neighboring Pacific islands, Chamorro has stronger linguistic ties to the Philippines and Indonesia than to the Oceanic languages spoken across most of the Pacific. Linguists classify it within the Western Malayo-Polynesian branch, and its grammar shares structural features with Philippine languages, including a complex verb system that shifts depending on whether a speaker is describing something that has happened or something that might happen.
Centuries of Spanish colonial rule, beginning in the 1600s, left a heavy imprint on the vocabulary. Massive borrowing from Spanish introduced hundreds of loanwords, and to a lesser degree, Philippine languages also contributed vocabulary. Today, Chamorro is spoken alongside English on Guam and in the CNMI, though fluency has declined among younger generations.
Traditional Social Structure
Chamorro society was, and in many ways remains, matrilineal. Children belong to their mother’s clan, and inheritance passes through the maternal line. A man became head of his clan through his mother, and the highest-ranking woman in each clan, typically the firstborn daughter, served as a female clan leader of equal status to the male leader. Her children oversaw internal clan affairs.
Villages contained multiple clans, but not all clans held equal standing. A clan’s status depended on its prestige and the behavior of its leaders. Land was traditionally owned by the clan as a collective, not by individuals. This system was disrupted first by Spanish colonization and later when the United States took control of Guam and claimed more than half the island’s land for military purposes.
Inafa’maolek: The Core Cultural Value
At the heart of Chamorro social life is the concept of inafa’maolek, which translates to “making good to each other.” It describes a person’s responsibility to maintain harmony within their family and community, emphasizing interdependence over individualism. Rather than a simple call for niceness, Chamorro scholars describe it as a complex social relationship that seeks balance through acts of both contribution and retribution.
Since the 1970s, inafa’maolek has taken on political significance as well. CHamoru intellectual Robert A. Underwood invoked the concept during the early self-determination movement to remind both indigenous Chamorros and non-indigenous residents of their mutual responsibility to each other and to the island. Today, activist groups continue to use inafa’maolek as a framework for opposing what they see as destructive U.S. military expansion on Guam, calling instead for rebuilt mutual relationships between communities and the environment.
Colonial History and Its Consequences
Spain claimed the Mariana Islands in 1668, sending Jesuit missionaries to convert the Chamorro population. Tensions escalated into open warfare by June 1671 after a series of killings on both sides. The Spanish-Chamorro Wars lasted nearly 30 years, with the last military campaign occurring in 1695.
The consequences were devastating. Spanish authorities forced the destruction of roughly 180 rural settlements, concentrating the surviving population into a few large villages in a policy called reducción. Chamorros were required to submit to the Catholic Church, abandon traditional spiritual practices, and destroy ancestral skulls and other sacred objects. The indigenous population experienced a catastrophic decline. After the wars ended, the Chamorro people lost their political independence, much of their claim to the land, and large portions of their traditional culture and religion.
Spain ceded Guam to the United States following the Spanish-American War in 1898, while Germany purchased the northern islands. Japan took control of the northern Marianas during World War I, and the U.S. eventually administered the entire chain after World War II. In 1950, the Guam Organic Act granted U.S. citizenship to the Chamorro people, transferred Guam’s administration to the Department of the Interior, and allowed the island to elect its own legislature and establish its own court system.
Population Today
The 2020 U.S. Census counted 47,329 people living in the CNMI, with the Chamorro population representing the largest Native Hawaiian and Other Pacific Islander group. In the CNMI alone, 12,001 people identified as Chamorro with no additional racial or ethnic group, while 17,163 identified as Chamorro alone or in combination with another group. On Guam, Chamorros make up the single largest ethnic group, and a significant diaspora lives across the U.S. mainland, particularly in California, Washington state, and Texas.
Traditional Healing Practices
Chamorro medicine has its own class of traditional healers: the suruhåna (female) and suruhånu (male). These practitioners use herbal remedies, massage (called lasa), topical medicines applied to the skin (palai), medicinal teas, and dietary advice. Some specialize in treating women or children, while others focus on fertility issues. The practice also involves communicating with taotaomo’na, the spirits of ancestors, to address illnesses believed to have a supernatural origin.
One well-known preparation, called åmot makpong, combines 16 different roots and leaves. Traditional remedies draw on plants like noni, aloe vera, oregano, and several species native to the Marianas. Knowledge of these plants has historically been passed down within families, with children accompanying their mothers into the jungle to learn which herbs to gather and how to prepare them.
A Unique Health Mystery
For more than 150 years, the Chamorro population has experienced unusually high rates of a fatal neurological condition called lytico-bodig, which combines symptoms resembling both ALS (progressive paralysis) and Parkinson’s disease with dementia. The condition typically strikes in middle or later life. The leading scientific theory points to the seeds of the cycad plant, a native species traditionally ground into flour or used as topical medicine. Researchers have identified a neurotoxic amino acid in cycad seeds that, in primate studies, produced motor system disease. The suspected mechanism involves decades of latency between exposure and the onset of symptoms, which has made the connection difficult to prove definitively.