Historians and legal scholars generally agree that during John Marshall's tenure as chief justice of the United States Supreme Court from 1801 to 1835, the federal judiciary expanded its power to interpret the Constitution and asserted with increasing force its authority to speak on behalf of the Union. This single story of judicial nationalism, however, contains two distinct and largely non-overlapping strands. Historians have tended to focus on the Supreme Court alone, to the exclusion of the lower federal courts, and have largely treated early national controversies over the lower federal courts as outgrowths of the political turmoil that accompanied the emergence of the first party system. Legal scholars in the fields of federal courts and constitutional law, meanwhile, have devoted significant attention to the lower federal courts but have largely neglected the history of how those courts developed beyond the key early moments of the Constitutional Convention and the First Congress.