In 1861, President Abraham Lincoln pledged to amend a federal law granting only Christian clergy the right to serve as military chaplains. During the Civil War (in which 6,500 Jews served for the North, and another 2,000 for the South), a religious Jew named Michael Allen had been elected as the non-denominational chaplain of his army regiment. When Allen's Jewishness became "publicized," rather than subject his family to the humiliating ordeal of his dismissal, Allen resigned, citing poor health. The regiment then elected Rabbi Arnold Fischel as its chaplain, in order to test the constitutionality of the "Christian-only" law. Much lobbying ensued, including Fischel traveling to Washington to meet with Lincoln. Six months later, the law was amended to permit Jewish clergy to become military chaplains. It is regarded historically as the first case of American Jews successfully challenging federal legislation.