Wallis (Wallisian: ʻUvea) is a Polynesian atoll/island in the Pacific Ocean belonging to the French overseas collectivity (collectivité d'outre-mer, or COM) of Wallis and Futuna. It lies north of Tonga, northeast of Fiji, east-northeast of the Hoorn Islands, east of Fiji's Rotuma, southeast of Tuvalu, southwest of Tokelau and west of Samoa. Its area is almost 100 km² (39 sq mi) with 8,333 people. Its capital is Mata Utu. Roman Catholicism is the predominant religion. Its highest point is Mount Lulu Fakahega (131 metres, 430 ft). Wallis is of volcanic origin with fertile soil and some remaining lakes. Rainfall is plentiful.

It was part of the Tongan maritime empire from around the 13th to 16th century. By that time the influence of the Tuʻi Tonga had declined so much that ʻUvea became important in itself. The big fortress of Talietumu close to Lotoalahi in Mua was the last holdout of the Tongans until they were defeated. The island was renamed "Wallis" after a Cornish navigator, Captain Samuel Wallis, who saw it while sailing aboard HMS Dolphin on 16 August 1767. On 5 April 1842, the authorities of Wallis Island requested protection by France with a protectorate treaty signed in April 1887. After a referendum in 1959, Wallis became a French Overseas Territory in 1961.