Božidar Kantušer (Bozidar Kantuser) (December 5, 1921, Pavlovski Vrh, Slovenia – May 9, 1999, Paris) was a Slovene composer of classical music.

The rural environment, the cultural heritage and the nature of his native Prlekija, where he lived the first seven years, left a lasting impression on the composer.

The dances of masks of pagan origin (Kurenti) and the bonfire wheels of fire (Kresi) that he witnessed at the time opened for him the universe of fiction, a subject to which Kantušer dedicated several works, such the ballet Midsummer Night, which also uses another childhood memory, namely work rhythms specific to particular farming tasks.

Kantušer attended first grade (1928–29) in Ljutomer, after which the family moved to Celje, the father's birthplace and where he endorsed a cadastral employment.

The Kantušer children often spent the summer months at the foot of the Alps, in Kamnik, the birthplace of the composer's mother.

The Prelude and Fugue for piano is the only work of this period that Kantušer retained in his catalog (two orchestral scores remain unfindable).

He mingled with the artistic milieu and notably made friends with the painters Pranas Gailius, Raphael Kherumian, Veno Pilon and Emil Wachter.

In 1952 and 1953 Kantušer attended the classes by Olivier Messiaen as well as those by Tony Aubin and by Jean Rivier, at the Conservatoire de Paris.

In Fontainebleau, living near the forest (Villa Bois Couvert), Kantušer reconnected with nature, going for long walks.

In the second half of the 60s, he became friends with the conductor Jean-Jacques Werner, the organist Georges Devallée and Marc Lombard, and also had professional relationships with them during his entire career.

In summer 1966, they made a long bus trip across the USA and during that stay, Kantušer acquired American citizenship.

From then on the director of the BIMC, Kantušer devoted a large amount of time to this position which he remained in for more than thirty years.

In 1971, the Kantušers left Fontainebleau and returned to Paris, first living in the Bastille quarter, then Rue de Rome, and finally at the Cité internationale des arts where they stayed and where the couple met many artists.

In the 1970s, the family often spent summers in Grožnjan, where they joined an artist colony that revived that Istrian town, and where the composer notably reconnected with his friend Karel Zelenko.

EFM (Éditions françaises de musique) published the Cello Concerto, and in 1973, Kantušer signed his Third Symphony.

In 1977, the Society of Slovene Composers (EDSS) published Two Images and Kantušer signed Coexistence № 1,[10] which was premiered the same year in Opatija.

This suite was choreographed in 1979 by Majna Sevnik for Slovenian television (RTV Slovenija) under the title Midsummer Night (Kresna noč).

In 1985, Kantušer wrote Eppur si muove for string orchestra, which was premiered in 1986 at the Cankar Hall in Ljubljana.

In this decade, there were several publications and radio programs about the composer (notably on France 2), and three CD-ROMs including his works were stamped in Slovenia.

The talks were successful in 1999, Kantušer meeting the minister Jožef Školč and the town of Šmartno being chosen as the venue for the information center.

Grace Renzi took care of the succession of the BIMC and thanks to Dominique Hausfater the collection is now at the Médiathèque Hector Berlioz at the Conservatoire de Paris.