Nallur is an affluent suburb in Jaffna, Sri Lanka. It is located 3 km south from Jaffna city centre. Nallur is most famous for Nallur Kandaswamy temple, one of Sri Lanka's most sacred place of pilgrimage for Sri Lankan Hindus. Nallur is also famous for being the historical capital of the old Jaffna Kingdom and birthplace of renowned philosopher and theologian, Arumuka Navalar.

The Jaffna kingdom, also known as Kingdom of Aryachakravarti, was a historical kingdom of what today is northern Sri Lanka. It came into existence around the town of Jaffna on the Jaffna peninsula and was traditionally thought to have been established after the invasion of Kalinga Magha from Kalinga in India. Established as a powerful force in the north, northeast and west of the island, it eventually became a tribute-paying feudatory of the Pandyan Empire in modern South India in 1258, gaining independence when the last Pandyan ruler of Madurai was defeated and expelled in 1323 by Malik Kafur, the army general of the Delhi Sultanate. For a brief period in the early to mid-14th century it was an ascendant power in the island of Sri Lanka, to which all regional kingdoms accepted subordination. However, the kingdom was overpowered by the rival Kotte kingdom around 1450 when it was invaded by Prince Sapumal under the orders of Parakramabahu VI.