Joseph Jones Reynolds, United States Army general and commander of the Department of Texas during Reconstruction, was born at Flemingsburg, Kentucky, on January 4, 1822, the seventh child of Edward and Sarah (Longley) Reynolds. He briefly attended Wabash College, Crawfordsville, Indiana, before receiving an appointment to the United States Military Academy at West Point. He graduated in 1843, tenth in a class of thirty-nine. In 1845 he joined troops under Gen. Zachary Taylor in Texas. He returned the following year to West Point as an instructor of history and geography and stayed until 1855. On December 3, 1846, he married Mary Elizabeth Bainbridge. After a tour of duty in Indian Territory, he resigned his commission to teach engineering at Washington University in St. Louis. In 1860 he resettled in Indiana to enter the grocery business with his brother. At the outbreak of the Civil War Reynolds returned to duty as a colonel in a regiment of Indiana volunteers and was soon appointed brigadier general of United States Volunteers. He distinguished himself in the fight for western Virginia and was promoted in 1862 to major general. He commanded a division in the Army of the Cumberland at Chickamauga and in fighting near Chattanooga, organized the defense of New Orleans in 1864, and led the Nineteenth Corps in the capture of Mobile. Reynolds took charge of the Department of Arkansas at the end of the war and was subsequently transferred to Brownsville, where he assumed responsibility for the military subdistrict of the Rio Grande.
In September 1867 he succeeded Gen. Charles Griffin in command at Galveston of the Department of Texas. As he moved to secure control of the state by the Republican party, Reynolds quickly became caught up in the turmoil of political Reconstruction. Before the arrival of Democratic general Winfield S. Hancock as his superior in the Fifth Military District, Reynolds appointed more than 400 Unionists and Republicans to state offices. After completing a registration of Texas voters that disfranchised thousands of Democrats and former Confederates, Reynolds organized the election of delegates to the Constitutional Convention of 1868–69. In March 1869 his former classmate, President Ulysses S. Grant, appointed him to command the Fifth Military District, and apparently aroused Reynolds's interest in a United States Senate seat. The Republican party in Texas, however, emerged from the 1868 convention split between moderate and radical wings. As Reynolds curried the favor of first the moderate Republicans under A. J. Hamilton and then the radicals under E. J. Davis, he split the party further and weakened whatever support may have existed for his senatorial candidacy. In February 1870 he stepped aside as a candidate due to opposition from across the state and from across party lines. The termination of military rule in Texas in April 1870 effectively ended Reynolds's political career. Reynolds returned to military duties on the frontier in 1872, notably in a campaign against the Sioux and Northern Cheyenne Indians on the Powder River in Montana. The failure of that campaign led to his court-martial in 1876. Although the sentence resulting from the court's judgment against Reynolds was suspended, he resigned in 1877. He died in Washington, D.C., on February 25, 1899, and was survived by his wife, two sons, and two daughters.