Hagåtña, formerly Agana or Agaña, is a coastal village and the capital of the United States territory of Guam. From the 18th through mid-20th century, it was Guam's population center, but today, it is the second smallest of the island's 19 villages in both area and population. However, it remains one of the island's major commercial districts in addition to being the seat of government.

"Hagåt" (also romanized as haga', with a glottal stop instead of a syllable-final "t") means "blood" in the Chamorro language. The suffix "-ña" can be translated as either the possessive pronouns his, hers or its in English (cognate to -nya in Malay and Indonesian, and niya in Tagalog), or a signification of greater comparative degree, similar to some uses of the English suffix "-er". There is much speculation that the indigenous peoples originally migrated from the village of Agat/Hagåt. Therefore, "Hagåtña" can be translated "his or her blood" possibly meaning "related to him, her or it", or it could be translated to what might roughly mean "more Hagåt", as in, an extension of the village of Hagåt. It could also mean "better Hagåt", or "more than, surpassing or superior to Hagåt" in a sense of being "more Hagåt than Hagåt itself". In 1998, the Guam Legislature changed the name from "Agana" back to the original Chamorro form. However, the name of the neighboring village Agana Heights remains unchanged.

Hagåtña is located at the mouth of the Hagåtña River on Guam's west coast. According to the United States Census Bureau, the city has a total area of 1 square mile (2.6 km²). It is (by direction of travel) the westernmost state or territorial capital city of the United States. The village is bounded by the sandy beaches of Agana Bay to the north, the Hagåtña River and associated wetlands to the east, and a cliff (above which is the village of Agana Heights) to the South. Several high-rise office buildings are in the center of the village, while the western portion of the city known as Anigua is more residential. Unlike many villages, central Hagåtña is divided into city blocks with shops and small restaurants throughout the center of the village. Highly populated residential areas in the villages of Mongmong-Toto-Maite, Sinajana, and Agana Heights surround Hagåtña.

The city has a tropical rainforest climate (Köppen: Af) similar to that found in the Amazon Basin. Rainfall is high especially from June to November, reaching 978 millimeters (38.50 in) in a single month in August 1997, whilst the year 2004 was the wettest in history with 3,539 millimeters (139.33 in).

Hagåtña was a prominent village before Guam's colonization by the Spanish. In 1668, the first Spanish missionary led by the Spanish priest San Vitores and his team arrived on the island. The colonizers proselytized and forced the indigenous Chamorro people to convert to Christianity, in many cases without consent. One of those who converted, Chief Kepuha, donated land in Hagåtña enabling San Vitores to build the first church (Dulce Nombre de Maria Cathedral-Basilica) on Guam, which was used by San Vitores to further colonize the indigenous peoples and their lands.

Under Spanish rule, and particularly the Spanish-Chamorro Wars, much of the indigenous population of Guam and other Mariana Islands were forced to relocate to the city after a genocide was instigated and conducted by the Spanish, led by San Vitores, against the indigenous population. The remains of buildings from the Spanish administration can be seen in the Plaza de España located beside the cathedral of the Archdiocese of Agaña. The remains of the Spanish Governor's Palace is here and is closer to the Department of Education than the Cathedral.

After Guam was ceded by Spain to the United States in the Spanish–American War of 1898, Hagåtña remained the seat of government under U.S. Naval Administration. By 1940, the city's population had grown to about 10,000 containing nearly half of the island's residents. Villages had been established nearby for immigrants from the Caroline Islands.

Guam was captured by Japanese forces on December 8, 1941. The Japanese renamed Guam to Ōmiya-jima (Japanese: 大宮島), or Great Shrine Island, and Hagåtña to Akashi (Japanese: 明石), or Bright Stone. During Guam's 1944 liberation from the Japanese during World War II, the city was heavily damaged by U.S. naval bombardment. Many former residents settled in other parts of Guam after the war. As part of Guam's reconstruction plan, the U.S. Navy constructed new, straight city streets that passed through existing lots and created many plots of land with multiple owners. This has hindered the development of the city to the present day. In December 1944, Guam was the scene of the Agana race riot, between black and white servicemen stationed on the island.