<Table> <Tr> <Th_colspan="2"> Name </Th> <Th> Term </Th> <Th> Position </Th> </Tr> <Tr> <Td> </Td> <Td> John Langdon </Td> <Td> April 6--21, 1789 </Td> <Td> President pro tempore </Td> </Tr> <Tr> <Td> </Td> <Td> John Adams </Td> <Td> April 21, 1789--March 4, 1797 </Td> <Td> President of the Senate </Td> </Tr> <Tr> <Td> </Td> <Td> Thomas Jefferson </Td> <Td> March 4, 1797--March 4, 1801 </Td> <Td> President of the Senate </Td> </Tr> <Tr> <Td> </Td> <Td> Aaron Burr </Td> <Td> March 4, 1801--March 4, 1805 </Td> <Td> President of the Senate </Td> </Tr> <Tr> <Td> </Td> <Td> George Clinton </Td> <Td> March 4, 1805--April 20, 1812 </Td> <Td> President of the Senate </Td> </Tr> <Tr> <Td> </Td> <Td> William H. Crawford </Td> <Td> April 20, 1812--March 4, 1813 </Td> <Td> President pro tempore </Td> </Tr> <Tr> <Td> </Td> <Td> Elbridge Gerry </Td> <Td> March 4, 1813--November 23, 1814 </Td> <Td> President of the Senate </Td> </Tr> <Tr> <Td> </Td> <Td> John Gaillard </Td> <Td> November 25, 1814--March 4, 1817 </Td> <Td> President pro tempore </Td> </Tr> <Tr> <Td> </Td> <Td> Daniel Tompkins </Td> <Td> March 4, 1817--March 4, 1825 </Td> <Td> President of the Senate </Td> </Tr> <Tr> <Td> </Td> <Td> John C. Calhoun </Td> <Td> March 4, 1825--December 28, 1832 </Td> <Td> President of the Senate </Td> </Tr> <Tr> <Td> </Td> <Td> Hugh Lawson White </Td> <Td> December 28, 1832--March 4, 1833 </Td> <Td> President pro tempore </Td> </Tr> <Tr> <Td> </Td> <Td> Martin Van Buren </Td> <Td> March 4, 1833--March 4, 1837 </Td> <Td> President of the Senate </Td> </Tr> <Tr> <Td> </Td> <Td> Richard Mentor Johnson </Td> <Td> March 4, 1837--March 4, 1841 </Td> <Td> President of the Senate </Td> </Tr> <Tr> <Td> </Td> <Td> John Tyler </Td> <Td> March 4--April 4, 1841 </Td> <Td> President of the Senate </Td> </Tr> <Tr> <Td> </Td> <Td> Samuel L. Southard </Td> <Td> April 4, 1841--May 31, 1842 </Td> <Td> President pro tempore </Td> </Tr> <Tr> <Td> </Td> <Td> Willie P. Mangum </Td> <Td> May 31, 1842--March 4, 1845 </Td> <Td> President pro tempore </Td> </Tr> <Tr> <Td> </Td> <Td> George M. Dallas </Td> <Td> March 4, 1845--March 4, 1849 </Td> <Td> President of the Senate </Td> </Tr> <Tr> <Td> </Td> <Td> Millard Fillmore </Td> <Td> March 4, 1849--July 9, 1850 </Td> <Td> President of the Senate </Td> </Tr> <Tr> <Td_colspan="4"> Vacant July 9--11, 1850 </Td> </Tr> <Tr> <Td> </Td> <Td> William R. King </Td> <Td> July 11, 1850--December 20, 1852 </Td> <Td> President pro tempore </Td> </Tr> <Tr> <Td> </Td> <Td> David Rice Atchison </Td> <Td> December 20, 1852--March 4, 1853 </Td> <Td> President pro tempore </Td> </Tr> <Tr> <Td> </Td> <Td> William R. King </Td> <Td> March 4--April 18, 1853 </Td> <Td> President of the Senate </Td> </Tr> <Tr> <Td> </Td> <Td> David Rice Atchison </Td> <Td> April 18, 1853--December 4, 1854 </Td> <Td> President pro tempore </Td> </Tr> <Tr> <Td> </Td> <Td> Lewis Cass </Td> <Td> December 4, 1854 </Td> <Td> President pro tempore </Td> </Tr> <Tr> <Td> </Td> <Td> Jesse D. Bright </Td> <Td> December 5, 1854--June 9, 1856 </Td> <Td> President pro tempore </Td> </Tr> <Tr> <Td> </Td> <Td> Charles E. Stuart </Td> <Td> June 9--10, 1856 </Td> <Td> President pro tempore </Td> </Tr> <Tr> <Td> </Td> <Td> Jesse D. Bright </Td> <Td> June 11, 1856--January 6, 1857 </Td> <Td> President pro tempore </Td> </Tr> <Tr> <Td> </Td> <Td> James Murray Mason </Td> <Td> January 6--March 4, 1857 </Td> <Td> President pro tempore </Td> </Tr> <Tr> <Td> </Td> <Td> John C. Breckinridge </Td> <Td> March 4, 1857--March 4, 1861 </Td> <Td> President of the Senate </Td> </Tr> <Tr> <Td> </Td> <Td> Hannibal Hamlin </Td> <Td> March 4, 1861--March 4, 1865 </Td> <Td> President of the Senate </Td> </Tr> <Tr> <Td> </Td> <Td> Andrew Johnson </Td> <Td> March 4--April 15, 1865 </Td> <Td> President of the Senate </Td> </Tr> <Tr> <Td> </Td> <Td> Lafayette S. Foster </Td> <Td> April 15, 1865--March 2, 1867 </Td> <Td> President pro tempore </Td> </Tr> <Tr> <Td> </Td> <Td> Benjamin Wade </Td> <Td> March 2, 1867--March 12, 1868 </Td> <Td> President pro tempore </Td> </Tr> <Tr> <Td> </Td> <Td> Salmon P Chase </Td> <Td> March 13--May 26, 1868 </Td> <Td> Chief Justice </Td> </Tr> <Tr> <Td> </Td> <Td> Benjamin Wade </Td> <Td> May 27, 1868--March 3, 1869 </Td> <Td> President pro tempore </Td> </Tr> <Tr> <Td> </Td> <Td> Schuyler Colfax </Td> <Td> March 4, 1869--March 4, 1873 </Td> <Td> President of the Senate </Td> </Tr> <Tr> <Td> </Td> <Td> Henry Wilson </Td> <Td> March 4, 1873--November 22, 1875 </Td> <Td> President of the Senate </Td> </Tr> <Tr> <Td> </Td> <Td> Thomas W. Ferry </Td> <Td> November 22, 1875--March 4, 1877 </Td> <Td> President pro tempore </Td> </Tr> <Tr> <Td> </Td> <Td> William A. Wheeler </Td> <Td> March 4, 1877--March 4, 1881 </Td> <Td> President of the Senate </Td> </Tr> <Tr> <Td> </Td> <Td> Chester A. Arthur </Td> <Td> March 4--September 19, 1881 </Td> <Td> President of the Senate </Td> </Tr> <Tr> <Td_colspan="4"> Vacant September 19--October 10, 1881 </Td> </Tr> <Tr> <Td> </Td> <Td> Thomas F. Bayard </Td> <Td> October 10--13, 1881 </Td> <Td> President pro tempore </Td> </Tr> <Tr> <Td> </Td> <Td> David Davis III </Td> <Td> October 13, 1881--March 3, 1883 </Td> <Td> President pro tempore </Td> </Tr> <Tr> <Td> </Td> <Td> George F. Edmunds </Td> <Td> March 3, 1883--March 3, 1885 </Td> <Td> President pro tempore </Td> </Tr> <Tr> <Td> </Td> <Td> Thomas A. Hendricks </Td> <Td> March 4, 1885--November 25, 1885 </Td> <Td> President of the Senate </Td> </Tr> <Tr> <Td_colspan="4"> Vacant November 25--December 7, 1885 </Td> </Tr> <Tr> <Td> </Td> <Td> John Sherman </Td> <Td> December 7, 1885--February 26, 1887 </Td> <Td> President pro tempore </Td> </Tr> <Tr> <Td> </Td> <Td> John James Ingalls </Td> <Td> February 26, 1887--March 3, 1889 </Td> <Td> President pro tempore </Td> </Tr> <Tr> <Td> </Td> <Td> Levi P. Morton </Td> <Td> March 4, 1889--March 4, 1893 </Td> <Td> President of the Senate </Td> </Tr> <Tr> <Td> </Td> <Td> Adlai E. Stevenson I </Td> <Td> March 4, 1893--March 4, 1897 </Td> <Td> President of the Senate </Td> </Tr> <Tr> <Td> </Td> <Td> Garret Hobart </Td> <Td> March 4, 1897--November 21, 1899 </Td> <Td> President of the Senate </Td> </Tr> <Tr> <Td> </Td> <Td> William P. Frye </Td> <Td> November 21, 1899--March 4, 1901 </Td> <Td> President pro tempore </Td> </Tr> <Tr> <Td> </Td> <Td> Theodore Roosevelt </Td> <Td> March 4--September 14, 1901 </Td> <Td> President of the Senate </Td> </Tr> <Tr> <Td> </Td> <Td> William P. Frye </Td> <Td> September 14, 1901--March 4, 1905 </Td> <Td> President pro tempore </Td> </Tr> <Tr> <Td> </Td> <Td> Charles W. Fairbanks </Td> <Td> March 4, 1905--March 4, 1909 </Td> <Td> President of the Senate </Td> </Tr> <Tr> <Td> </Td> <Td> James S. Sherman </Td> <Td> March 4, 1909--October 30, 1912 </Td> <Td> President of the Senate </Td> </Tr> <Tr> <Td> </Td> <Td> Augustus Octavius Bacon </Td> <Td> October 30--December 15, 1912 </Td> <Td> President pro tempore (rotating) </Td> </Tr> <Tr> <Td> </Td> <Td> Jacob Harold Gallinger </Td> <Td> December 16, 1912--January 4, 1913 </Td> <Td> President pro tempore (rotating) </Td> </Tr> <Tr> <Td> </Td> <Td> Augustus Octavius Bacon </Td> <Td> January 5--18, 1913 </Td> <Td> President pro tempore (rotating) </Td> </Tr> <Tr> <Td> </Td> <Td> Jacob Harold Gallinger </Td> <Td> January 19--February 1, 1913 </Td> <Td> President pro tempore (rotating) </Td> </Tr> <Tr> <Td> </Td> <Td> Augustus Octavius Bacon </Td> <Td> February 2--15, 1913 </Td> <Td> President pro tempore (rotating) </Td> </Tr> <Tr> <Td> </Td> <Td> Jacob Harold Gallinger </Td> <Td> February 16--March 4, 1913 </Td> <Td> President pro tempore (rotating) </Td> </Tr> <Tr> <Td> </Td> <Td> Thomas R. Marshall </Td> <Td> March 4, 1913--March 4, 1921 </Td> <Td> President of the Senate </Td> </Tr> <Tr> <Td> </Td> <Td> Calvin Coolidge </Td> <Td> March 4, 1921--August 2, 1923 </Td> <Td> President of the Senate </Td> </Tr> <Tr> <Td> </Td> <Td> Albert B. Cummins </Td> <Td> August 2, 1923--March 4, 1925 </Td> <Td> President pro tempore </Td> </Tr> <Tr> <Td> </Td> <Td> Charles G. Dawes </Td> <Td> March 4, 1925--March 4, 1929 </Td> <Td> President of the Senate </Td> </Tr> <Tr> <Td> </Td> <Td> Charles Curtis </Td> <Td> March 4, 1929--March 4, 1933 </Td> <Td> President of the Senate </Td> </Tr> <Tr> <Td> </Td> <Td> John Nance Garner </Td> <Td> March 4, 1933--January 20, 1941 </Td> <Td> President of the Senate </Td> </Tr> <Tr> <Td> </Td> <Td> Henry A. Wallace </Td> <Td> January 20, 1941--January 20, 1945 </Td> <Td> President of the Senate </Td> </Tr> <Tr> <Td> </Td> <Td> Harry S. Truman </Td> <Td> January 20--April 12, 1945 </Td> <Td> President of the Senate </Td> </Tr> <Tr> <Td> </Td> <Td> Kenneth McKellar </Td> <Td> April 12, 1945--January 4, 1947 </Td> <Td> President pro tempore </Td> </Tr> <Tr> <Td> </Td> <Td> Arthur H. Vandenberg </Td> <Td> January 4, 1947--January 3, 1949 </Td> <Td> President pro tempore </Td> </Tr> <Tr> <Td> </Td> <Td> Kenneth McKellar </Td> <Td> January 3--20, 1949 </Td> <Td> President pro tempore </Td> </Tr> <Tr> <Td> </Td> <Td> Alben W. Barkley </Td> <Td> January 20, 1949--January 20, 1953 </Td> <Td> President of the Senate </Td> </Tr> <Tr> <Td> </Td> <Td> Richard Nixon </Td> <Td> January 20, 1953--January 20, 1961 </Td> <Td> President of the Senate </Td> </Tr> <Tr> <Td> </Td> <Td> Lyndon B. Johnson </Td> <Td> January 20, 1961--November 22, 1963 </Td> <Td> President of the Senate </Td> </Tr> <Tr> <Td> </Td> <Td> Carl Hayden </Td> <Td> November 22, 1963--January 20, 1965 </Td> <Td> President pro tempore </Td> </Tr> <Tr> <Td> </Td> <Td> Hubert Humphrey </Td> <Td> January 20, 1965--January 20, 1969 </Td> <Td> President of the Senate </Td> </Tr> <Tr> <Td> </Td> <Td> Spiro Agnew </Td> <Td> January 20, 1969--October 10, 1973 </Td> <Td> President of the Senate </Td> </Tr> <Tr> <Td> </Td> <Td> James Eastland </Td> <Td> October 10--December 6, 1973 </Td> <Td> President pro tempore </Td> </Tr> <Tr> <Td> </Td> <Td> Gerald Ford </Td> <Td> December 6, 1973--August 9, 1974 </Td> <Td> President of the Senate </Td> </Tr> <Tr> <Td> </Td> <Td> James Eastland </Td> <Td> August 9--December 19, 1974 </Td> <Td> President pro tempore </Td> </Tr> <Tr> <Td> </Td> <Td> Nelson Rockefeller </Td> <Td> December 19, 1974--January 20, 1977 </Td> <Td> President of the Senate </Td> </Tr> <Tr> <Td> </Td> <Td> Walter Mondale </Td> <Td> January 20, 1977--January 20, 1981 </Td> <Td> President of the Senate </Td> </Tr> <Tr> <Td> </Td> <Td> George H.W. Bush </Td> <Td> January 20, 1981--July 13, 1985 </Td> <Td> President of the Senate </Td> </Tr> <Tr> <Td> </Td> <Td> Strom Thurmond </Td> <Td> July 13, 1985 </Td> <Td> President pro tempore </Td> </Tr> <Tr> <Td> </Td> <Td> George H.W. Bush </Td> <Td> July 13, 1985--January 20, 1989 </Td> <Td> President of the Senate </Td> </Tr> <Tr> <Td> </Td> <Td> Dan Quayle </Td> <Td> January 20, 1989--January 20, 1993 </Td> <Td> President of the Senate </Td> </Tr> <Tr> <Td> </Td> <Td> Al Gore </Td> <Td> January 20, 1993--January 7, 1999 </Td> <Td> President of the Senate </Td> </Tr> <Tr> <Td> </Td> <Td> William Rehnquist </Td> <Td> January 8--February 12, 1999 </Td> <Td> Chief Justice </Td> </Tr> <Tr> <Td> </Td> <Td> Al Gore </Td> <Td> February 13, 1999--January 20, 2001 </Td> <Td> President of the Senate </Td> </Tr> <Tr> <Td> </Td> <Td> Dick Cheney </Td> <Td> January 20, 2001--June 29, 2002 </Td> <Td> President of the Senate </Td> </Tr> <Tr> <Td> </Td> <Td> Robert Byrd </Td> <Td> June 29, 2002 </Td> <Td> President pro tempore </Td> </Tr> <Tr> <Td> </Td> <Td> Dick Cheney </Td> <Td> June 29, 2002--July 21, 2007 </Td> <Td> President of the Senate </Td> </Tr> <Tr> <Td> </Td> <Td> Robert Byrd </Td> <Td> July 21, 2007 </Td> <Td> President pro tempore </Td> </Tr> <Tr> <Td> </Td> <Td> Dick Cheney </Td> <Td> July 21, 2007--January 20, 2009 </Td> <Td> President of the Senate </Td> </Tr> <Tr> <Td> </Td> <Td> Joe Biden </Td> <Td> January 20, 2009--January 20, 2017 </Td> <Td> President of the Senate </Td> </Tr> <Tr> <Td> </Td> <Td> Mike Pence </Td> <Td> January 20, 2017--present </Td> <Td> President of the Senate </Td> </Tr> </Table> <Tr> <Th_colspan="2"> Name </Th> <Th> Term </Th> <Th> Position </Th> </Tr> <Tr> <Td> </Td> <Td> John Langdon </Td> <Td> April 6--21, 1789 </Td> <Td> President pro tempore </Td> </Tr> <Tr> <Td> </Td> <Td> John Adams </Td> <Td> April 21, 1789--March 4, 1797 </Td> <Td> President of the Senate </Td> </Tr>

Who is the head officer of the senate