Claus Wilhelm Nicolai Dunger is a Swedish singer and acoustic songwriter from Piteå in Sweden.

He has released twelve EPs and albums, singing primarily in English, and collaborated notably with Will Oldham, the Esbjörn Svensson jazz trio and Ebbot Lundberg.

A former association football player, Nicolai was signed by the Telegram label of Warner records, releasing two albums that did not sell enough copies to enable him to give up his part-time job as a gardener.

A meeting with Ebbot Lundberg of the Swedish band The Soundtrack of Our Lives led to two further albums, a tour with Emilíana Torrini and the use of one of his songs in an advertisement for an oil company.

He has featured on both Nina Persson's second "A Camp" record, and on Maia Hirasawa's album GBG vs STHLM.