Hagatna is 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.

Hagatna was a prominent village before Guam's colonization by the Spanish. In 1668, the first Spanish missionary, Padre San Vitores arrived on the island. The family of Chief Kepuha donated land in Hagatna enabling San Vitores to build the first church (Dulce Nombre de Maria Cathedral-Basilica) on Guam.

Under Spanish rule, much of the indigenous population of Guam and other Mariana Islands was forced to relocate to the city. The remains of buildings from the Spanish administration can be seen in the Plaza de España located beside the cathedral of the Archdiocese of Agana. 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, 'Agana' 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. Today, despite a resident population of only 1,100 (less than 1% of Guam's total), the city remains the seat of the territorial government.

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