Giovanni "Gianni" Sanjust was a Roman clarinetist whose career had two halves that ran side by side: a jazz life that began in the early 1950s Dixieland scene and lasted until his death in 2020, and a second life in the Italian record industry as a lyricist, occasional pop singer and, for Ricordi and others, a producer. He was born in Rome on June 23, 1934, into a family of the Sardinian nobility, and taught himself the clarinet.

In 1952 he formed the Traditional Dixielanders with trombonist Peppino De Luca and played with them until 1955, when he joined the Seconda (II) Roman New Orleans Jazz Band, which he stayed with until 1960, when Lucio Dalla replaced him, according to Italian Wikipedia. The band was led by bassist Carlo Loffredo, and Sanjust plays clarinet on its RCA Italiana recordings from 1957 to 1962: the 1957 LP Parlando Di Storia, the 1959 singles "Petite Fleur," "By The Light Of The Silvery Moon" and "Yes, We Have No Bananas," and the 1961 LP Noi Le Suoniamo Così, on which he also sings. He plays clarinet on Loffredo's 1961 ... Blues From Rome! and again on the 1967 Cetra LP Whisky E Dixie, where Loffredo's band backs the singer Jula De Palma.

From 1960 to 1962 he played with pianist Romano Mussolini. Discogs credits him with clarinet on one track of Mussolini's 1958 RCA LP with Nunzio Rotondo and Lilian Terry, and on the first five tracks of the 1962 Ricordi LP Jazz Allo Studio 7, recorded in Milan on April 21 and 24, 1962 by the Romano Mussolini All Stars with trumpeter Cicci Santucci, trombonist Dino Piana, tenor saxophonist Enzo Scoppa, Loffredo and drummer Franco Tonani. He is also a credited performer, with Enzo Randisi, on Mussolini's undated R.M. Record LP Swing Swing Swing. In 1961, under the billing Gianni Sanjust E Il Suo Complesso, he led the Cetra EP Jazz '61, a set made for the centenary of Italian unification, with Enrico Rava on trumpet, according to Discogs.

After his years with Mussolini he moved to Milan for a post at Dischi Ricordi and, as Italian Wikipedia puts it, joined the city's traditional-jazz groups. The same years brought his other career. Between 1963 and 1965 he recorded seven singles for CBS, among them "Un Vecchio Clarino" (1963, with an orchestra led by Giorgio Gaslini), "Tu Verrai Da Me," "Vecchio Sole," a clarinet version of "Dardanella," and "Ti Scorderai Di Me," his entry in the RAI song contest Un Disco Per L'Estate in 1965. As a lyricist he supplied Italian words for Bobby Solo ("Una Granita Di Limone" is the title Italian Wikipedia names), for the beat group Quelli, and for Milva, on whose records Discogs credits him 37 times and his pseudonym Rompigli several more; he is also credited on Wilma Goich's "Finalmente" (1968) and on the Italian text of "Il Ballo Di Simone," the local version of "Simon Says." Discogs lists 342 appearance credits for him and 18 as producer, mostly on pop records. As Ricordi's artistic director and later an independent producer he worked with Franco Califano, Mia Martini and Mietta, and he co-wrote Nek's "Angeli Nel Ghetto" with Antonello de Sanctis and Gabriele Varano.

In 1977 he returned to Rome and resumed a jazz career "almost full time," in the words of Italian Wikipedia, alongside his production work. His later recordings are all in the jazz and swing tradition. On May 13 and 14, 1987 he recorded Italian Clarinet Summit in Milan with clarinetist Bruno Longhi, guitarist Lino Patruno, pianist Riccardo Zegna, vibraphonist Enzo Randisi, bassist Rosario Bonaccorso and drummer Walter Ganda. He played in Lino Patruno's Jazz Stars of Italy, the all-star traditional band that also held Loffredo and Mussolini, and is the clarinetist on The Big Reunion (1990), Live In San Marino (1995) and the compilation Hello Satch! (2002). In the 1980s he made the YOR Record albums Gianni Sanjust And His Group (1985), with pianist Cinzia Gizzi, and Gianni Sanjust And His Band (1986), and with the pianist and arranger Riccardo Biseo he recorded three volumes of Napoli Jazz Sound (the first two issued in 2009 and 2010), jazz arrangements of Neapolitan songs from "'O Sole Mio" to "Malafemmena." He appears on the 2003 album Clarinetti Italiani beside Gianni Basso and pianist Rossano Sportiello, and in 2010 he recorded Alfredo Ferrario Meets Gianni Sanjust, a clarinet duet session with organ and drums, in Uboldo on March 17.

Italian Wikipedia also lists among the musicians he played with Chet Baker, Lee Konitz, Wild Bill Davison, Billy Butterfield, Ralph Sutton, Dan Barrett, Oscar Klein, Franco Ambrosetti and Eddy Palermo, besides Loffredo, Mussolini, Rava and others named above; none of the Baker, Konitz, Davison, Butterfield, Sutton, Barrett, Klein, Ambrosetti or Palermo sessions appears in his Discogs credits. The same article says he appeared in Sergio Leone's Once Upon a Time in America and wrote the score for an episode of the Steno film Capriccio All'Italiana, "Il Mostro Della Domenica." Sanjust died in Rome on January 9, 2020.

Sanjust was a New Orleans and swing clarinetist of the Italian traditional-jazz revival. His early records with the Roman New Orleans Jazz Band play the Dixieland canon ("Maple Leaf Rag," "Canal Street Blues," "When The Saints Go Marchin In," "Petite Fleur"), his 1960s sessions with Mussolini move to a mainstream bop-flavoured repertoire ("Jordu," "San Thomas"), and his later records return to swing standards ("Mood Indigo," "Crazy Rhythm," "Strike Up The Band"). He also sang on several of the Roman band's records, and his 1963 to 1965 CBS singles are vocal pop songs rather than jazz. Discogs tags his jazz releases Dixieland and Swing and his CBS singles Pop and Vocal. Most of his sheer credit count, lyrics and production, is in Italian pop, and it is the reason a search of his name returns Bobby Solo and Mia Martini records before it returns his clarinet; his instrumental identity throughout, from the 1957 RCA sessions to the 2010 Ferrario duets, is jazz.