High Quality Content by WIKIPEDIA articles! Jeremiah Sullivan Black (January 10, 1810 August 19, 1883) was an American statesman and lawyer. He was the son of Representative Henry Black, and the father of writer and Lieutenant Governor of Pennsylvania Chauncey Forward Black. He was largely self-educated, and before he was of age was admitted to the Pennsylvania bar. He gradually became one of the leading American lawyers, and from 1851 to 1857 was a member of the Supreme Court of Pennsylvania, serving as chief justice from 1851 to 1854. In 1857 he entered the Cabinet of President James Buchanan as Attorney General. In this capacity he successfully contested the validity of the California land claims to about 19,000 square miles (49,000 km²) of land, fraudulently alleged to have been granted to land-grabbers and others by the Mexican government prior to the close of the Mexican American War. From December 17, 1860 to March 4, 1861 he was Secretary of State. Perhaps the most influential of President Buchanan's official advisers, he denied the constitutionality of secession, and urged that Fort Sumter be properly reinforced and defended.