July 23, 1866: Judicial Circuits Act, Sess. 1, ch. 210, 14 Stat. 209, reduced the number of United States circuit courts to nine and the number of Supreme Court justices to seven
July 25, 1866: An Act to revive the grade of General in the United States Army, Sess. 1, ch. 232, 14 Stat. 223, (now called "4-star general"); Lieutenant General Ulysses S. Grant became the first to have this rank.
July 28, 1866: Metric Act of 1866, Sess. 1, ch. 301, 14 Stat. 339, legalized the use of the metric system for weights and measures in the United States.
July 28, 1866: Washington City Colored Schools Lots Donation Act ("An Act donating certain Lots in the City of Washington for Schools for Colored Children in the District of Columbia"), Sess. 1, ch. 308, 14 Stat. 343
March 2, 1867: Reconstruction Act, ch. 153, 14 Stat. 428 established five military districts, each headed by a general, in ten states of the former Confederate South (Tennessee excepted), and stipulates conditions for re-admission of these States into the Union.
March 2, 1867: Tenure of Office Act, ch. 154, 14 Stat. 430 required the president to obtain the Senate's advice and consent to suspend or dismiss certain federal public officials (notably cabinet officers). Violation of this act will lead to the impeachment of Andrew Johnson by the next (40th) Congress in 1868.
June 13, 1866: Approved an amendment to the Constitution addressing citizenship rights and equal protection of the laws, and submitted it to the state legislatures for ratification[1]
July 24, 1866: Tennessee readmitted to representation.
March 1, 1867: Nebraska admitted as the 37th state, sess. 2, ch. 36, 14 Stat. 391 (over president's veto)
Party summary
The count below identifies party affiliations at the beginning of the first session of this Congress, and includes members from vacancies and newly admitted states, when they were first seated. Changes resulting from subsequent replacements are shown below in the "Changes in membership" section.
Senate
During this Congress, two seats were added for the new state of Nebraska.
House of Representatives
During this Congress, one seat was added for the new state of Nebraska.
This list is arranged by chamber, then by state. Senators are listed in order of seniority, and representatives are listed by district.
Senate
Senators were elected by the state legislatures every two years, with one-third beginning new six-year terms with each Congress. Preceding the names in the list below are Senate class numbers, which indicate the cycle of their election. In this Congress, Class 1 meant their term began in the last Congress, requiring reelection in 1868; Class 2 meant their term began in this Congress, requiring reelection in 1870; and Class 3 meant their term ended in this Congress, requiring reelection in 1866.
Skip to House of Representatives, below
House of Representatives
The names of members of the House of Representatives are preceded by their district numbers.
Changes in membership
The count below reflects changes from the beginning of the first session of this Congress.
Lists of committees and their party leaders for members of the House and Senate committees can be found through the Official Congressional Directory at the bottom of this article. The directory after the pages of terms of service lists committees of the Senate, House (Standing with Subcommittees, Select and Special) and Joint and, after that, House/Senate committee assignments. On the committees section of the House and Senate in the Official Congressional Directory, the committee's members on the first row on the left side shows the chairman of the committee and on the right side shows the ranking member of the committee.
Senate Journal, First Forty-three Sessions of Congress
House Journal, First Forty-three Sessions of Congress
Biographical Directory of the U.S. Congress
U.S. House of Representatives: House History
U.S. Senate: Statistics and Lists
Congressional Directory for the 39th Congress, 1st Session. 1866.
Congress, United States (1867). Congressional Directory for the 39th Congress, 2nd Session.
Transcripts of debates and proceedings
The Congressional Globe contains the official transcripts and proceedings of the Thirty-Ninth Congress, although newspapers often provided their own transcripts that sometimes differed from the official ones. Following are external links to the pertinent volumes of the Globe, which are downloadable and/or searchable via Google Books and HathiTrust:
The congressional debates pertaining to the Fourteenth Amendment can be found at “Congressional Debates of the Fourteenth Amendment to the United States Constitution”.