Palmyra Atoll ( /pælˈmaɪrə/) is an essentially unoccupied equatorial Northern Pacific atoll administered as an unorganized incorporated territory by the United States federal government. The variable temporary population of 4–20 "non-occupants" are essentially staff and scientists employed by various departments of the US government and The Nature Conservancy, as well as a rotating mix of Palmyra Atoll Research Consortium scholars pursuing research.

Palmyra is one of the Northern Line Islands (southeast of Kingman Reef and north of Kiribati Line Islands), located almost due south of the Hawaiian Islands, roughly halfway between Hawaii and American Samoa. The atoll is 4.6 sq mi (12 km²), and it is located in the equatorial Northern Pacific Ocean. Its 9 mi (14 km) of coastline has one anchorage known as West Lagoon.

The atoll consists of an extensive reef, two shallow lagoons, and some 50 sand and reef-rock islets and bars covered with vegetation—mostly coconut trees, Scaevola, and tall Pisonia trees.

Palmyra (Aramaic: ܬܕܡܘܪܬܐ‎;Hebrew: תדמור‎; tiḏmor, Greek: Παλμύρα, Arabic: تدمر‎; Tadmur, English pronunciation: /ˌpælˈmaɪrə/) was an ancient city in central Syria. In antiquity, it was an important city located in an oasis 215 km northeast of Damascus and 180 km southwest of the Euphrates at Deir ez-Zor. It had long been a vital caravan stop for travellers crossing the Syrian desert and was known as the Bride of the Desert. The earliest documented reference to the city by its Semitic name Tadmor, Tadmur or Tudmur (which means "the town that repels" in Amorite and "the indomitable town" in Aramaic) is recorded in Babylonian tablets found in Mari.

Though the ancient site fell into disuse after the 16th century, it is still known as Tadmor in Arabic (aka Tedmor), and there is a newer town of the same name next to the ruins. The Palmyrenes constructed a series of large-scale monuments containing funerary art such as limestone slabs with human busts representing the deceased.

Palmyrans bore Aramaic names, and worshipped a variety of deities from Mesopotamia (Marduk and Ruda), Syria (Hadad, Baʿal, Astarte), Arabia (Allāt) and Greece (Athena). Palmyrans were originally speakers of Aramaic but later shifted to the Greek language. At the time of the Islamic conquests Palmyra was inhabited by several Arab tribes, primarily the Qada'ah and Kalb.