The Causes of the Civil War | Pennsylvania Civil War 150
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Pennsylvania Civil War 150

Pennsylvania Civil War 150


The Causes of the Civil War

The Issue

Many people today think that the desire by Northerners to abolish slavery was the sole cause of the Civil War. While it was the central issue, the cause of the War was much more complex. European settlements in the northern and southern colonies had followed different patterns of development: immigrants came from different places and classes in Europe; the economic base differed, with the North becoming more industrial by the mid-1800s than the South; and these different economies required different kinds of workers (from those legally enslaved through those who were employed in mills). As the Unites States expanded across the continent, settlers from the East Coast brought their institutions and values with them. Some of the settlers of the new territories, therefore, wanted to continue to use slavery and others did not.

The continuation of slavery and the slave trade had been an issue at the Constitutional Convention of 1787. During those discussions, it was apparent that some people felt that the issue should be decided by each state, rather than by the central government. In this way, each state could both preserve its unique culture and society as well as retain governmental power over its economy. Throughout the late 1790s and first half of the 1800s, various federal and state laws and court cases were passed that tried to either allow or control the expansion of slavery. Other legal acts protected with the rights of slaveholders, helped preserve an agricultural economy, or safeguarded states’ rights. While many Pennsylvanians were against slavery, they did not all share the same ideas on how to abolish slavery, or whether is should be abolished by federal law

The causes of the Civil War are often summarized then as the abolition of slavery on moral grounds, the expansion of slavery into the West, cultural and economic differences between the states (or sectional differences) and states’ rights to determine their own laws. Likewise the Civil War itself has been seen as a movement to rid the country of slavery, to preserve the Constitution as written, to preserve States’ rights, and to preserve the Union.

A Research Question

How would Pennsylvanians at the time describe the causes of the Civil War?

Read the Central Documents: Federal and Pennsylvania Laws and analyze the interaction of cultural, economic, geographic, political and social relations in creating these documents (Competency 1).

  • Create a timeline that shows how the restriction or expansion of slavery was affected over time by these legal actions.
  • Chart which favored an industrial (northern) economy and which an agricultural (southern) one.
  • Group the legal actions by which support the right of the federal government to decide the slavery questions and which the right of the states to decided for themselves.

Read the primary and secondary sources for an individual listed below (Competency 2).

  • Based upon the biographies, determine what point-of-view the person had about slavery, its expansion, and the way in which the federal government should be involved with the slavery question.
  • Describe how this person was directly involved with the passage of any of the legal actions listed under “Legal Documents.” If the person was not directly involved, hypothesize based upon that person’s views what s/he might have thought of these actions.
  • Synthesize the information and your informed opinion about this person’s point-of-view to write a statement from his/her perspective on the cases of the Civil War.

Repeat for other individuals listed to learn how Pennsylvanians in the mid-1800s would have understood the causes of the Civil War. (Competencies 3 and 4)

  • Which individuals held similar view on the causes of the War?
  • What might account for differing points-of-view?

Present the causes for the War in written, oral, or graphic form (Competency 5).

  • Each student presents what s/he now thinks the cause(s) of the Civil War were, supporting her/his point-of-view with primary sources.
  • The class as a whole might stage a debate about the causes of the War.


John McClintock (1814-1870)

Use with documents from Rights of Slave Owners

David Wilmot (1814-1868)

Use with documents: the Missouri Compromise, the Wilmot Proviso, and 14th Amendment

James Buchanan (1791-1868)

Use with documents on Tariffs and Western Expansion and Slavery

Martin Delaney (1824-1885)

Use with documents from Setting the Scene and Abolition of Slavery

Thaddeus Stevens (1792-1868)

Use with documents from Rights of Slave Owners and Abolition of Slavery

William Bigler (1814-1880)

Use with documents from Western Expansion and Slavery

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