Register of the Department of State contains a list of persons employed in the department and in the diplomatic, consular and territorial service of the United States. These 38 volumes cover 1870 to 1950 showing the names and salaries of the staff of the Department of State. They are freely available and can be searched.
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1870 [ digital copy ] [ searchable full text copy ]
1871 [ digital copy ] [ searchable full text copy ]
1872 [ digital copy ] [ searchable full text copy ]
1874 [ digital copy ] [ searchable full text copy ]
1892 [ digital copy ] [ searchable full text copy ]
1893 [ digital copy ] [ searchable full text copy ]
1910 [ digital copy ] [ searchable full text copy ]
1911 [ digital copy ] [ searchable full text copy ]
1912 [ digital copy ] [ searchable full text copy ]
1913 [ digital copy ] [ searchable full text copy ]
1914 [ digital copy ] [ searchable full text copy ]
1915 [ digital copy ] [ searchable full text copy ]
1916 [ digital copy ] [ searchable full text copy ]
1917 [ digital copy ] [ searchable full text copy ]
1918 [ digital copy ] [ searchable full text copy ]
1922 [ digital copy ] [ searchable full text copy ]
1924 [ digital copy ] [ searchable full text copy ]
1925 [ digital copy ] [ searchable full text copy ]
1926 [ digital copy ] [ searchable full text copy ]
1927 [ digital copy ] [ searchable full text copy ]
1928 [ digital copy ] [ searchable full text copy ]
1929 [ digital copy ] [ searchable full text copy ]
1930 [ digital copy ] [ searchable full text copy ]
1931 [ digital copy ] [ searchable full text copy ]
1932 [ digital copy ] [ searchable full text copy ]
1933 [ digital copy ] [ searchable full text copy ]
1934 [ digital copy ] [ searchable full text copy ]
1935 [ digital copy ] [ searchable full text copy ]
1936 [ digital copy ] [ searchable full text copy ]
1937 [ digital copy ] [ searchable full text copy ]
1938 [ digital copy ] [ searchable full text copy ]
1939 [ digital copy ] [ searchable full text copy ]
1940 [ digital copy ] [ searchable full text copy ]
1941 [ digital copy ] [ searchable full text copy ]
1942 [ digital copy ] [ searchable full text copy ]
1946 [ digital copy ] [ searchable full text copy ]
1948 [ digital copy ] [ searchable full text copy ]
1950 [ digital copy ] [ searchable full text copy ]