Charles Moïse Léon Salzedo (6 April 1885 – 17 August 1961) was a French harpist, pianist, composer and conductor. His compositions presented the harp as a virtuoso instrument. He influenced many composers with his new ideas for the harp's sounds, and was influential in New York's new music scene through his work leading the International Composers' Guild with Edgard Varèse.

Salzedo began studying at the Paris Conservatory at age nine and won the premier prix in harp and piano when he was just 16. He started his solo recital career at age 18, and was brought to the United States of America six years later, to perform as solo harpist with the Metropolitan Opera House in New York City. He toured extensively with the Trio de Lutèce, with Georges Barrère, flute and Paul Kéfer, cello. After being drafted into the French Army during World War I, Salzedo returned to the United States and continued touring with the trio.

In consultation with Vaslav Nijinsky during a summer in Maine, together they developed a system of esthetic gestures to be used while performing on the harp. Subsequently, he was instrumental in raising money to save Nijinsky by funding his residence in a Swiss Sanatorium. Aside from touring with his trio, he organized The Salzedo Harp Ensemble, utilizing his students, which toured extensively, often in collaboration with singers from the Metropolitan Opera.

He co-founded the International Composers' Guild with Edgard Varèse in 1921, and founded the National Harp Association to promote the harp. In addition to forming a summer harp colony, first in Seal Harbor, then later in Camden, Maine, he founded the harp department at the Curtis Institute of Music in 1924. He continued to teach privately in New York City until his death. He developed new techniques and notations for these techniques, which he used extensively in his compositions after 1919.

Carlos Salzedo was born Charles Moïse Léon Salzedo on 6 April 1885, in Arcachon, France. Salzedo's parents, Isaac Gaston Salzedo and Thérèse Judith Anna Silva, who resided in Bayonne, were vacationing in Arcachon when Mme. Salzedo fell down a flight of stairs, causing the two-month premature birth of Salzedo. Both parents were of noted Sephardic (Iberian Jewish) families and fine musicians, he a singer, she a pianist. Their first child, Marcel, became a violinist, and military band leader in Paris, and later in Côte d'Azur. During this time, Mme. Salzedo was employed as the summer-court pianist to Queen Mother Maria Christina in Biarritz. Young Léon-Charles played the piano for Maria Christina at the age of three, which led her to dub him "my little Mozart."

Salzedo's mother died just two years later when he was five. The family then moved to Bordeaux and a Basque woman, Marthe Tatibouet Bidebérripé, was hired to care for and help raise the children. Salzedo became deeply attached to her, and liked to think of himself as being culturally Basque. Some writers have attributed his fondness for five-beat rhythms to Basque traditions where they are often used. Léon-Charles, having begun playing piano by the age of three, wrote his first composition, a polka called Moustique (Mosquito), which was published when he was just five years old. Though lost, the theme reappeared in the Polka of his Suite of Eight Dances. At seven, he entered the St. Cecilia School of Music of Bordeaux, where he won first prize in piano and solfège three years later, after which the family moved to Paris. Léon-Charles entered the Paris Conservatory at age nine, where he again won prizes in piano and solfège. He continued his piano studies with Charles de Bériot, son of the renowned violinist Charles de Bériot and a pupil of Thalberg.

Salzedo's father, by then a respected voice teacher, decided Salzedo should take up a second instrument, and the harp was chosen because he was felt to be too weak to play a wind instrument, and his older brother Marcel already played the violin. Beginners were not accepted at the Conservatoire, so Carlos took lessons from a chanced-upon teacher, Marguerite Achard. After a few months, he had advanced enough that he was accepted as a pupil by Alphonse Hasselmans, professor of harp at the Conservatoire. After a year of study with Hasselmans, he entered the Conservatoire as a fully fledged harp pupil at the age of thirteen. In 1901, at age sixteen, Salzedo won the premier prix in harp and piano on the same day, an accomplishment unmatched to this day, and was awarded a Steinway grand piano. While a student, Salzedo freelanced as second harpist in the Orchestre Lamoureux as well as the orchestras of the Olympia theater and the Folies Bergère. The director of the Conservatoire, Gabriel Fauré, approved Salzedo for a counterpoint class after he wrote a Bach fugue from memory.

When Salzedo graduated, he was hired as a solo harpist, first orchestral harpist, and solo pianist at the New Casino in Biarritz under conductor/composer Piero Luigini. The following winter he toured Europe with the Concerts Colonne orchestra, followed by solo appearances as pianist and harpist with that orchestra. He made his Paris recital debut at age 18 as a harpist and pianist, in 1903, for which occasion he decided to change his name to Carlos from Léon-Charles Moise. About this time, a stroke paralyzed Gaston Salzedo, who handed over his position as synagogue music director to young Carlos. Salzedo also toured in solo performances around Europe, receiving glowing praise in the papers.