Harold Wilson conspiracy theories
Since the mid-1970s, a variety of conspiracy theories have emerged regarding British Labour Prime Minister Harold Wilson, who served as the Prime Minister of the United Kingdom from 1964 to 1970 and 1974 to 1976, winning four general elections. These range from Wilson having been a Soviet agent (a claim which MI5 investigated and found to be false), to Wilson being the victim of treasonous plots by conservative-leaning elements in MI5, claims which Wilson himself made.
James Wilson (Secretary of Agriculture)
Wilson rose to national prominence in early 1897 when newly elected President William McKinley nominated him as his Secretary for Agriculture. During sixteen consecutive years of Republican administrations, Presidents McKinley, Theodore Roosevelt and William Howard Taft retained him in that position. It was not until March 1913, following the election of a Democratic president (Woodrow Wilson) that Wilson left that office. In all, Wilson served as Secretary of Agriculture from March 6, 1897 to March 5, 1913 — the longest duration served by any American cabinet official. The length of Wilson's tenure is attributed to not only the same political party occupying the White House in three consecutive administrations, but also the similarity in political philosophy among the three Presidents under which Wilson served. Given the state of national politics which developed in the 20th and 21st centuries, it is unlikely any Cabinet member will exceed Wilson's mark.