Blum was born to immigrant German parents who discouraged him from pursuing a career in art. However, at sixteen Blum quit high school to work as an apprentice lithographer at the Cincinnati firm of Gibson and Co. He began night classes at the McMicken School of Design and, soon after, at the Ohio Mechanics' Institute, where he studied from life under Frank Duveneck. His fellow students included Alfred Brennan, Kenyon Cox and John Twachtman. Blum developed an early fascination with the work of Spanish artist Mariano J.M.B. Fortuny, whose sparkling, iridescent paint surfaces long remained an influence.
In 1876, Blum, Brennan, and Cox moved to Philadelphia for a short time. They studied at the Pennsylvania Academy of the Fine Arts under the conservative but tolerant Christian C. Schussele. A far greater influence, however, was the Japanese exhibit at the Centennial fair, which Blum visited. His lifelong interest in Japanese art and life ultimately led him to a pioneering two-year visit to that country begun in 1890.
After nine months in Philadelphia, Blum returned to Cincinnati to experiment with the medium of etching. Disenchanted with what he perceived as philistinism in his hometown, he left for New York in 1878 and obtained work as an illustrator for St. Nicholas and Scribner's Monthly magazines. Always an experimenter in media, Blum received critical acclaim for "impressionistic" water colors he showed in the 1879 exhibition of the American Water Color Society. In 1880, he again had an opportunity to develop his etching technique when he met Whistler in Venice during his first trip to Europe. He also spent time with Duveneck in Venice, as well as with the other American artists assembled there around Duveneck.
On his return to New York that year, Blum moved into the Sherwood Studio Building, but the next two summers were again spent in Europe. He and his traveling companions, J. Carroll Beckwith, William Merritt Chase, and William J. Baer, spent months in Venice, Spain, and Holland. Blum again wished to see Venice in 1884, but an outbreak of cholera kept him temporarily in Zandvoort, Holland, with Chase and Charles Ulrich. However he returned to Venice in 1886, 1887 and 1889.
Blum's paintings of Venetian subjects were well received for their flickering light and brightly patterned surfaces. Although membership in the Academy is not predicated on individual works, his Venetian Bead Stringers (Cincinnati Art Museum, Cincinnati, Ohio), shown in the 1888 Academy annual, was generally thought to have been the spur to his election as an Associate.
When he was not abroad, Blum was an active participant in the New York art world. He was elected to the Society of American Artists in 1882, and a year later, he helped found the Society of Painters in Pastel and served as its first president. He served on the Academy's Council from 1895 to 1898. From 1896 to 1900, Blum taught morning classes at the Art Students League, and he taught a class in painting from the model at the Academy school for the season of 1900-01.
Blum's long awaited trip to Japan came in 1890. He was commissioned for a series of drawings to illustrate articles on Japan by Sir Edwin Arnold which appeared in Scribners. While there, he also worked in oil and pastel.
Upon his return, he established a fruitful relationship with patron Alfred Corning Clark, who bought over thirty pictures by him. In 1893, Clark completed building Mendelssohn Hall on West Fortieth Street, the home of the Mendelssohn Glee Club. He commissioned Blum to paint two murals for the hall. These large works, Moods to Music and The Vintage Festival (both now in the collection of the Brooklyn Museum, Brooklyn, New York), occupied him from 1893 to 1898. (In addition to several paintings recorded below, the artist's estate presented over thirty preparatory drawings for Moods to Music to the National Academy.)
When Blum died of pneumonia, he was at work on murals for the New Amsterdam Theatre. The Academy's memorial to him entered into the minutes, May 11, 1904, describes his last years: ". . . never of a robust constitution the life of his later years was a constant fight against a malady that, he himself thought, made him incapable of doing his best work for long periods and certainly took from him the joy of living."
