During the winter of 1873-74, Sargent honed his skills, convincing his father that it was well worth encouraging his artistic pursuits. They traveled together to Paris in the spring of 1874, so that John Singer Sargent could continue his studies in the art capital of Europe. He entered the Paris studio of Carolus-Duran in 1874, where he stayed as student and assistant until 1878. Carolus-Duran had great influence on John Singer’s art, dispensing with the traditional academic approach. Carolus-Duran's method emphasized skipping the step of making detailed sketches and heading straight to the canvas with a paintbrush. Sargent internalized these techniques; his later works would come to be recognized for their immediacy, emotional depth and refined technique. He lived in Paris until 1884.
In 1876, he visited America, and found that he was intensely drawn to travel. When he got back to Europe, he continued traveling, using his voyages as opportunities to study great works of art and try his hand at portraying diverse locations. In Spain, Sargent admired and copied the works of Diego Velásquez; in Venice, he cultivated an appreciation for its picturesque canals, to which he would return many times. Travel scenes would form a major element of his work.
In 1885, he settled in London following the stormy reception of his Madame Gautreau at the 1884 Paris Salon. In fact, Sargent's reputation took a turn for the worse with the exhibition of this portrait. Because it defied many of the accepted standards of the day, and was slightly risqué in its portrayal of a woman in a low-cut, nearly sleeveless dress, it turned many of his admirers against him. Today, Madame Gautreau is considered one of his most celebrated works.
John Singer Sargent was not discouraged. On a pair of trips to the United States in 1887 and 1890, he found that Americans were not averse to being painted by him, and many members of American high society sat for his portraits.
The turning point for Sargent's career in England came when he showed his Carnation, Lily, Lily, Rose (painted 1885-86) at the London Royal Academy. The piece, undeniably one of Sargent's masterpieces, incorporated Victorian themes and a calculated impressionist influence that depicted two girls lighting lanterns among flowers in spring. The English recognized the painting's greatness, and members of the elite were soon lining up to commission their own likenesses.
Although his portraits were highly praised, Sargent eventually grew tired of painting them. Sargent backed away from the portrait business between 1907 and 1910 to leave himself time to focus on other projects, in particular a set of murals for the Boston Public Library. He also increasingly turned his attention to watercolors around this time, forging a strong reputation for his work in that medium.
The coming of World War I changed Sargent's subject matter, for a time. Visiting the Western Front at the request of the British government, which had asked him to paint a scene commemorating the war, Sargent created Gassed, an appropriately dark work, which depicted soldiers enduring the deplorable conditions that marked life in the Great War.
John Singer Sargent passed away in his sleep on April 14, 1925, at the age of 69. He left behind a large body of work, including portraits, travel scenes, watercolors and impressionistic masterpieces that have defined his reputation into the current century; his works are still exhibited around the world.