Map of the boundaries of the United States courts of appeals (by color) and United States District Courts. All District Courts lie within the boundary of a single jurisdiction, usually in a state (heavier lines); some states have more than one District Court (lighter lines denote those jurisdictions)
In contrast to the Supreme Court, which was established by Article III of the Constitution, the district courts were established by Congress.[note 1] There is no constitutional requirement that district courts exist at all. Indeed, after the ratification of the Constitution, some opponents of a strong federal judiciary urged that, outside jurisdictions under direct federal control, like Washington, D.C., and the territories, the federal court system be limited to the Supreme Court, which would hear appeals from state courts. This view did not prevail, however, and the first Congress created the district court system that is still in place today.
There are other federal trial courts that have nationwide jurisdiction over certain types of cases, but the district court also has concurrent jurisdiction over many of those cases, and the district court is the only one with jurisdiction over civilian criminal cases.