Irvin McDowell (1818−85) was a Union general in the American Civil War. Born in Columbus, Ohio, he graduated from the United States Military Academy at West Point in 1838 and fought in the Mexican War of 1846−48. Early in the Civil War he was a brigadier general at the head of the Department of Northeastern Virginia, and thus was in command of the Union army at the First Battle of Bull Run in July 1861. He held several other commands during the war, and was promoted to major general for his outstanding performance at the Battle of Cedar Mountain in Culpeper County, Virginia, on August 9, 1862. The image is from an album of mostly Civil War-era portraits by the famous American photographer Matthew Brady (circa 1823‒96) that belonged to Emperor Pedro II of Brazil (1825‒91), a collector of photography as well as a photographer himself. The album was a gift to the emperor from Edward Anthony (1818‒88), another early American photographer who, in partnership with his brother, owned a company that in the 1850s became the leading seller of photographic supplies in the United States. Dom Pedro may have acquired the album during a trip to the United States in 1876 when he, along with President Ulysses S. Grant, opened the Centennial Exposition in Philadelphia. Brady was born in upstate New York, the son of immigrants from Ireland. Best known for his photographs documenting the battles of the American Civil War, he began his career in 1844 when he opened a daguerreotype portrait studio at the corner of Broadway and Fulton Streets in New York City. Over the course of the next several decades, Brady produced portraits of leading American public figures, many of which were published as engravings in magazines and newspapers. In 1858 he opened a branch in Washington, DC. The album, which also contains a small number of non-photographic prints, is part of the Thereza Christina Maria Collection at the National Library of Brazil. The collection is composed of 21,742 photos assembled by Emperor Pedro II throughout his life and donated by him to the national library. The collection covers a wide variety of subjects. It documents the achievements of Brazil and Brazilians in the 19th century and also includes many photographs of Europe, Africa, and North America.