Marcello Melis was a Sardinian double bassist and composer, one of the first musicians from the island to build a career in international jazz. He studied classical music at the Cagliari Conservatory, and in the late 1950s worked in a dance-hall group called I Lumi before moving to Rome, where he came into contact with the alternative music scene around the Folkstudio club. There he met saxophonist Mario Schiano, trombonist Giancarlo Schiaffini, and drummer Franco Pecori, and in 1966 the group founded the Gruppo Romano Free Jazz, one of the earliest dedicated free jazz ensembles in Italy. On Rome's jazz club circuit through the 1960s and 1970s, Melis accompanied a run of visiting American and international musicians, among them Steve Lacy, Mal Waldron, and Gato Barbieri. His work with Lacy is documented on record: Melis plays bass on Lacy's 1971 quartet album Moon, recorded in France with cellist Irene Aebi, clarinetist Claudio Volonte, and drummer Jacques Thollot.

Melis made his recording debut as a leader with Perdas De Fogu (1975, Vista), co-billed with Mario Schiano and recorded in New York with pianist Don Pullen, vocalist Sheila Jordan, guitarist Bruce Johnson, drummer Jerome Cooper, and percussionist Ray Mantilla. The album, whose title translates from Sardinian as "burning stones," set out the project that would define the rest of his career: putting Sardinian folk material inside an African-American free jazz idiom. He developed that idea fully on The New Village On The Left... (1977, Black Saint), his first fully solo-billed leader album, which combined traditional Sardinian singers, including the Gruppo Rubanu Orgosolo vocal quartet, with a jazz group of trumpeter Enrico Rava, trombonist Roswell Rudd, and drummer Famoudou Don Moye, all playing behind Melis's own bass and compositions.

The following year brought Free To Dance (1978, Black Saint), Melis's largest-cast leader recording: Lester Bowie and Enrico Rava on trumpet, George Lewis and Gary Valente on trombone, Don Pullen on piano, Fred Hopkins on bass alongside Melis, Nana Vasconcelos and Don Moye on percussion, and vocalists Sheila Jordan and Jeanne Lee. In between, he co-led Bars (1977, Musica Records) with baritone saxophonist Hamiet Bluiett and Don Moye, a stripped-down trio session recorded in New York. Angedras (1983, Black Saint), a four-part suite named for the mirror image of "Sardegna," the Italian name for Sardinia, dedicated the record's four movements to the elements of water, earth, air and fire, with Don Pullen, Don Moye, and alto saxophonist Sandro Satta; the cover photography was by Melis's wife, Nina Contini Melis, an internationally recognized jazz photographer who had curated jazz photo exhibitions. Melis's final album as a credited leader was Uncaged (1991, Splasc(H) Records), a fully improvised session billed jointly to Mario Schiano, Don Moye, Melis, and Giancarlo Schiaffini, a reunion of several of his earliest Roman collaborators recorded two decades after the Gruppo Romano Free Jazz.

Melis died in Paris on October 5, 1994, of cancer, at age 55.

Melis's music was built on a deliberate fusion: the sound of Sardinian shepherd songs, launeddas-tradition melody, and the island's vocal polyphony set directly against the vocabulary of American free jazz. That combination runs through his entire leader catalog, from the New York sessions of Perdas De Fogu through the Sardinian-vocalist collaboration of The New Village On The Left... to the elemental suite structure of Angedras. His working method leaned on a small, recurring circle of American free jazz musicians, most consistently drummer Famoudou Don Moye and pianist Don Pullen, both of whom appear on four of his five leader and co-leader albums, giving his catalog a level of personnel continuity unusual for an Italian bandleader of the period working across three different labels and a decade and a half.