Kronger studied at the Museum of Fine Arts School in Boston under Frank Benson and Edmund Tarbell (1886-1894) and spent a year at the Art Students League in New York under William Merritt Chase (1889-90). At the completion of his studies in Boston, he won the Longfellow Travelling Scholarship which enabled him to go to Paris where he studied at the Academie Julian under Laurens and Constant (1894-97).
While in Paris, Kronberg came under the influence of the Impressionists, especially Degas. Like that French master, he was a devotee of the theatre and took many of his subjects from the ballet. He painted many important stage personalities, both in Paris and New York. A trip to Spain in 1920 resulted in the painting Spanish Dancer which was exhibited at the Paris Salon of 1921, an event which led to his election to the Salon Nationale des Beaux Arts in 1922. Later that same year, other of his Spainish paintings were exhibited at Knoedler's Gallery in New York.
Isabella Stewart Gardner purchased a number of Kronberg's works during his lifetime, including La Gitana (The Gypsy) which was painted in Seville in 1920. Two designs for fans, another interest of Kronberg's, are also in the Gardner collection. Later, Kronberg served as an advisor to Mrs. Gardner as she built her collection of old masters and contemporary works.
Kronberg maintained studios in Boston, New York, and Paris for most of his career, and a number of summers were spent in Gloucester, Massachusetts. He was awarded the Medal of Honor at the Paris International Exposition in 1937 and was earned the Legion of Honor medal in 1950.
