Taʻū is the largest inhabited island in the Manuʻa Islands in American Samoa and the easternmost volcanic island of the Samoan Islands. In the early 19th century, the island was sometimes called Opoun.
Taʻū is well known as the site where the American anthropologist Margaret Mead conducted her dissertation research in Samoa in the 1920s, after which she published her findings in a work titled Coming of Age in Samoa. Ta’u also has the highest mountain in American Samoa, Mount Lata, as well as 21 square kilometers (8.3 sq mi) of National Park lands, and 3.9 km (1.5 sq mi) of waters separated by some of the tallest sea cliffs in the world.