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O'Sullivan, Timothy Henry
American, 1840-1882

Timothy H. O'Sullivan (c. 1840 – January 14, 1882) was a photographer prominent for his work on subjects in the American Civil War and the Western United States.

O'Sullivan was born in either Ireland or New York City. As a teenager, he was employed by Mathew Brady. When the Civil War began he was commissioned a first lieutenant in the U.S. Army and over the next few years, he fought in Beaufort, Port Royal, Fort Walker, and Fort Pulaski. After being honorably discharged, he rejoined Brady's team. In July 1862 O'Sullivan followed the campaign of Gen. John Pope's Northern Virginia Campaign. In July 1863, he created his most famous photograph, "The Harvest of Death", depicting dead soldiers from the Battle of Gettysburg. In 1864, following Gen. Ulysses S. Grant's trail, he photographed the Siege of Petersburg and the siege of Fort Fisher. That brought him to the Appomattox Court House, the site of Robert E. Lee's surrender in April 1865.

From 1867 to 1869 he was official photographer on the United States Geological Exploration of the 40th Parallel under Clarence King, which began at Virginia City, Nevada, where he photographed the mines, and worked eastward. His job was to photograph the West to attract settlers. O'Sullivan's pictures were among the first to record the prehistoric ruins, Navajo weavers, and pueblo villages of the Southwest. In 1870 he joined a survey team in Panama to survey for a canal across the isthmus. From 1871 to 1874 he returned to the southwestern United States to join Lt. George M. Wheeler's survey west of the One Hundredth Meridian. He faced starvation on the Colorado River when some of expedition's boats capsized; few of the 300 negatives he took survived the trip back East. He spent the last years of his short life in Washington, D.C., as official photographer for the U.S. Geological Survey and the Treasury Department. He died in Staten Island of tuberculosis at age 42.