Theresa Hill Arriola (also known as Isa Arriola) is a Northern Mariana Islander cultural anthropologist and Indigenous rights activist from Saipan, who lectures in critical Indigenous studies in the department of sociology and anthropology at Concordia University. She is also the chair of Our Common Wealth 670, an organisation that advocates for demilitarisation of the Pacific territories of the United States.
Arriola was born in Saipan in the Northern Mariana Islands and is Chamorro. She attended the Northern Marianas Academy. She studied at Brown University for a BA in History, then for her MA in Anthropology from the University of Hawaiûi. She studied for her doctorate at University of California at Los Angeles (UCLA) and graduated in 2021. Her thesis explored the how militarism intersects with Indigenous identities and the environment in the NMI, with a particular focus on the Chamorro and Refaluwasch peoples. In 2017 she was awarded a grant by the Wenner-Gren Foundation to explore the overlapping territorial claims made by the Indigenous Chamorro people and the US military.
In 2018 she joined the Board of the Northern Marianas Humanities Research Council, and has held the positions of Vice-Chair, Secretary and Treasurer. As of 2021 she is Assistant Professor of Critical Indigenous Studies in the Department of Sociology and Anthropology at Concordia University. She is a member of the Association for Social Anthropologists in Oceania.
She is Chair of Our Common Wealth 670, an organisation that advocates for "demilitarisation throughout the Marianas archipelago". She has argued publicly that levels of American military involvement in the region are unsustainable. She has also voiced concern that the US military will look at the Mariana archipelago as an alternative location for its military bases on Guam. The organisation, led by Arriola, has encouraged opposition to the US Navy's plans to extend destructive military training in the region.