Julius Rosenwald (August 12, 1862 – January 6, 1932) was a Jewish American business executive and philanthropist. He was the long-time president and an owner of Sears, Roebuck and Company, a large and successful Chicago-based national retailer in the early 20th century. His Rosenwald Fund donated millions in matching funds to promote Black American education. Together with Booker T Washington, they built close to 5,000 schools, many of them in the segregated south and provided fellowships to close to one thousand grantees. In 1919 Rosenwald was appointed to the Chicago Commission on Race Relations. He was the principal founder and benefactor of the Museum of Science and Industry, serving as president from 1927 to 1932.

Julius Rosenwald was born in 1862 in Springfield, Illinois, to the clothier Samuel Rosenwald and his wife Augusta (Hammerslough), a Jewish immigrant couple from Germany, who arrived in the US with 20 dollars in his pocket. Julius Rosenwald was Samuel and Augusta’s second child to survive infancy. He was born and raised just a few blocks from Abraham Lincoln's residence in Springfield, Illinois, during Lincoln's presidency. In 2020, the house, formerly known as Lyon House, was renamed in his honor, and a plaque erected.

Additionally, Samuel Rosenwald served as the president of the B’rith Sholom synagogue of the Springfield Hebrew Congregation, where Julius received a Jewish education and learned lifelong lessons about the importance of "tzedakah" or charity, and "tikkun olam" or repairing the world, which shaped his values.

By his sixteenth year, Rosenwald was apprenticed by his parents to his uncles in New York City to learn the clothing trades. While in New York, he befriended Henry Goldman and Henry Morgenthau Sr. With his younger brother Morris, Rosenwald started a clothing manufacturing company.

Rosenwald had heard about other clothiers who had begun to manufacture clothing according to standardized sizes from data collected during the American Civil War. He decided to try the system but to move his manufacturing facility closer to the rural population that he anticipated would be his market. He and his brother moved to Chicago, Illinois.

In 1890, Rosenwald married Augusta "Gussie" Nusbaum, a daughter of a competing clothier. Together they had five children: Lessing J. Rosenwald, Adele (Rosenwald) Deutsch Levy, Edith (Rosenwald) Stern, Marion (Rosenwald) Ascoli―second wife of Italian American journalist Max Ascoli―and William Rosenwald. Their son, Lessing Rosenwald, became a prominent businessman, following his father in the chairmanship of Sears, Roebuck & Company (1932–1939). William was also a successful businessman and philanthropist who created the United Jewish Appeal and established the William Rosenwald Family Fund. Edith married businessman Edgar B. Stern Sr.

One of his grandchildren is Nina Rosenwald. Another was the Hollywood film producer Armand Deutsch, who believed that he was the intended target of the thrill killers Leopold and Loeb, who kidnapped and murdered his schoolmate Robert "Bobby" Franks on May 21, 1924.

In 1893, Richard Sears and Alvah C. Roebuck renamed their watch company Sears, Roebuck & Company and began to diversify. Rosenwald and Weil was a principal supplier of men's clothing for Sears, Roebuck. The volumes of unsold merchandise caused by the Panic of 1893 and his declining health led Roebuck to leave the company.