What percentage of Republicans voted for the 13th Amendment?

explain the thirteenth amendment: Definition and quick facts

The Thirteenth Amendment abolished slavery in the United States and completed state ratification on December 6, 1865, after congressional passage in 1864 and 1865, a settled documentary milestone recorded by the National Archives and related exhibits National Archives featured document.

The clear legal outcome was the constitutional prohibition of slavery and involuntary servitude except as punishment for crime. That legal change followed documented votes in Congress and a sequence of state ratifications described in Library of Congress timelines and exhibits Library of Congress ratification timeline.

Congressional passage and recorded vote totals

The U.S. Senate recorded final passage of the amendment on April 8, 1864 with a roll-call total of 38 yeas and 6 nays, as summarized on the Senate Art and History site Senate Art and History and on the Senate overview page Senate passes the Thirteenth Amendment.

The U.S. House of Representatives recorded its final passage on January 31, 1865 with a roll-call total of 119 yeas and 56 nays; the House Historian provides the roll-call list and contextual notes for that vote House Historian roll-call summary.

Those chamber-level totals are authoritative for the overall congressional outcome, but deriving party percentages requires consulting the lists that record each member’s vote and party label (see the House voting process for how roll calls are recorded).

Primary roll-call records and where to find them

The House Historian transcriptions and the Senate Art and History roll-call pages list individual members, their recorded votes, and often give contextual notes about contested or absent seats; these primary pages are the right starting point for counting party-level support House Historian roll-call list (see also the NYPL roll-call item NYPL roll call and our primary-source verification guide).

For machine-readable aggregation and reproducible counts, datasets such as Voteview collate historical roll-call records with party labels and make them available for analysis Voteview roll-call datasets; the Library of Congress also maintains relevant digital collections LOC digital collections.

When you download a roll-call list, check whether the transcription includes a clear party column and whether any members are listed with labels such as Unionist or National Union that may need careful classification.

Step-by-step method to calculate the percentage of Republicans who voted yes

Follow a simple, reproducible routine that uses the House or Senate primary roll-call list as the authoritative source and records every step. The method below treats the House lists as an example but applies equally to the Senate.

1. Obtain the official roll-call transcription from the House Historian or the Senate Art and History page, or download the Voteview dataset if you prefer a machine-readable file. Use the page that transcribes names, votes, and any party labels House Historian roll-call list.

2. Create a single table with columns for Member Name, Recorded Vote (Yea/Nay/Present/Not Voting), Party Label as given on the roll call, and any notes about contested seats or absence.

3. Decide in advance how to treat members listed under labels like Unionist or National Union. Record those decisions in a methods note so readers can see whether you counted them as Republican, Democratic, or separate categories.

4. Count the number of members labelled Republican who recorded a Yea vote. Record the denominator as the total number of members labelled Republican present on that roll call after your documented inclusion rules.

5. Compute the percentage with the formula: Republican yes percentage = (Republican yes votes / Republican total counted) * 100. Note any excluded or ambiguous cases in a short appendix or methods note.

Practical calculation example and citation wording

Below is a non-numeric example workflow using the House roll-call as the source to illustrate how to report a computed percentage without inventing or asserting new totals. Begin with a citation to the roll-call page you used, then replace placeholders with your computed numbers; for example, According to the House Historian roll-call list, X of Y members labelled Republican voted yea on January 31, 1865, where X and Y are the counts you computed from the table House Historian roll-call.

When you publish the figure, add a short caveat about membership changes during the Civil War and any labeling decisions. For example, public records show that some members used National Union or Unionist labels and some Confederate seats were vacant, which affects the denominator used in party percentage calculations Library of Congress context.

Political and wartime context that shaped the vote

The Civil War context matters for interpreting party percentages because many Confederate representatives were absent or excluded, changing the effective party composition in both chambers; historians and reference works note that wartime alignments shaped which members were present to vote Encyclopaedia Britannica overview.

Some members identified under the National Union banner or as Unionists rather than as straight Republicans or Democrats. When counting, researchers should document how those labels were treated and cite the primary roll-call pages as the basis for any reclassification House Historian notes.

Common mistakes and pitfalls when reporting party percentages

A frequent error is inferring party-level support from chamber totals without consulting the roll-call lists. Chamber totals show overall yeas and nays but not how each party’s members voted, so they are not sufficient for a party percentage claim Senate roll-call summary.

Another pitfall is misclassifying members who are listed under nonstandard labels or who changed affiliation. Use the original roll-call label if possible and document any reassignments used for counting; if you use a secondary dataset, note that in your methods Voteview data.

Practical scenarios for readers and journalists

If you need a House-only percentage, use the House Historian roll-call transcription as your authoritative source and document how you treated Unionist or vacancy cases; then calculate the Republican yes share using the formula in the step-by-step section House roll-call.

If you want a combined House and Senate percentage, compile both chamber roll-call lists, apply consistent classification rules for party labels in each chamber, and present both chamber-level percentages plus a combined figure with a clear methods note about harmonization choices Senate roll-call.

When publishing a small table, include a model caption such as: Source: House Historian roll-call list and Senate Art and History roll-call; counts reflect members labelled Republican on each primary roll call, with Unionist labels counted as described in notes.

How to attribute and cite primary sources correctly

Use direct citations to the House Historian or Senate Art and History roll-call pages when you report counts. For example: House roll-call: U.S. House of Representatives, Office of the Historian, Thirteenth Amendment roll-call, accessed [date] House Historian roll-call (see also our constitutional rights hub).

For contextual claims about ratification dates or the amendment text, cite the National Archives featured document or the Library of Congress ratification timeline and include an access date in your source list National Archives featured document.

What percentages of Republican members tell us and what they do not

Calculated percentages show how a partisan bloc voted on a roll call but do not by themselves explain motives or the causes of the vote; percentages are descriptive measures and should be presented with contextual notes about wartime alignments and absences Britannica context.

Primary roll-call lists indicate that a majority of Republican members in both chambers supported the amendment, but the precise share attributed to Republicans requires the counting method described above and should be reported as a documented result, not as an attribution of motive House Historian roll-call.

Further research steps and resources

For downloadable roll-call data and machine-readable files, check Voteview and the congressional archives; Voteview provides datasets useful for reproducible counts and is commonly used for party-level aggregations Voteview datasets.

For primary documentary context, consult the National Archives featured document and the Library of Congress exhibition pages, and contact the House or Senate historical offices for clarifications on ambiguous entries or contested seats National Archives featured document.

Short summary and suggested reporting lines

Three-sentence summary: The Thirteenth Amendment abolished slavery and was ratified by the states in December 1865, after congressional passage in 1864 and 1865. The Senate recorded final passage on April 8, 1864 (38 yeas, 6 nays) and the House on January 31, 1865 (119 yeas, 56 nays), as the official roll calls show. To report what percentage of Republican members voted yes, use the primary roll-call lists and the counting method outlined above National Archives featured document.

Model lead paragraph: According to the House Historian roll-call list, X of Y members labelled Republican voted yea on the Thirteenth Amendment on January 31, 1865; replace X and Y with the computed counts and include a brief methods note describing how Unionist labels and absences were handled House roll-call.

Checklist: document sources, state party-label rules, record excluded members, and provide raw counts alongside computed percentages.

References and further reading (primary sources)

Primary pages for verification include the National Archives featured document and ratification timeline, the House Historian roll-call transcription, the Senate Art and History roll-call summary, and Voteview for downloadable data; consult those pages directly when reproducing counts National Archives featured document.

Endnotes: When you publish counts, include access dates and a brief methods note explaining any reclassification of labels such as Unionist or National Union.