Haydn almost certainly encountered him as a child in a Hungarian castle, where the boy’s father was a servant and Haydn was the director of music, and Thomas Jefferson saw him performing in Paris in 1789: a 9-year-old biracial violin prodigy with a cascade of dark curls. While the boy would go on to inspire Beethoven and help shape the development of classical music, he ended up relegated to a footnote in Beethoven’s life.

Rita Dove, the Pulitzer Prize-winning former United States poet laureate, has now breathed life into the story of that virtuoso, George Augustus Polgreen Bridgetower, in her new book, “Sonata Mulattica” (W. W. Norton). The narrative, a collection of poems subtitled “A Life in Five Movements and a Short Play,” intertwines fact and fiction to flesh out Bridgetower, the son of a Polish-German mother and an Afro-Caribbean father.

When he died in South London in 1860, his death certificate simply noted that he was a “gentleman.” Ms. Dove imagines, as she writes in her poem “The Bridgetower,” that “this bright-skinned papa’s boy/could have sailed his fifteen-minute fame/straight into the record books.”

It did not help that years earlier, apparently in a fit of pique after a quarrel over a woman, Beethoven removed Bridgetower’s name from a sonata the composer had dedicated to him, Bridgetower being the mulatto of “Sonata Mulattica.” The two men had performed it publicly for the first time in Vienna in 1803, with Beethoven on piano and Bridgetower on violin.