Missouri Compromise

An agreement made between the South and North over slavery when Missouri joined the Union in the United States in 1819-21. Missouri was part of the land acquired in the Louisiana Purchase of 1803, and slavery had existed in the state since it was a French colony. At the time, there were an equal number of slave and free states, but the South held the upper house of the federal parliament, and the North held the upper house. In February 1819, the House of Representatives passed an amendment proposed by J. Talmadge of New York, which made the gradual abolition of slavery in the region a condition for Missouri's admission into the Union, but the Senate rejected it. After a fierce debate over slavery, a North-South compromise was reached in March 1820, with Maine, which had at the time applied to secede from Massachusetts and join the Union, becoming a free state, and Missouri being recognized as a slave state, but with the addition of an amendment by J. B. Thomas of Illinois stipulating that, with the exception of Missouri, no slave states would be established north of 36 degrees 30 minutes north latitude in the remaining part of the Louisiana Purchase.

After this, a clause in the state constitution drafted by Missouri that prohibited the immigration of free blacks into the state became an issue in the federal Congress. However, a compromise was reached again the following year, and Missouri was finally admitted to the Union on the condition that the state constitution did not include any clauses that would deprive the rights of U.S. citizens. Thus, the conflict between the North and the South was temporarily calmed, and the balance between slave states and free states was maintained until the Mexican War. However, after the Compromise of 1850, the Kansas-Nebraska Act of 1854 introduced the principle of popular sovereignty, which created the possibility of Kansas, located north of latitude 36 degrees 30 minutes, becoming a slave state, and the Missouri Compromise was invalidated.

[Tomoko Takemoto]

Source: Shogakukan Encyclopedia Nipponica About Encyclopedia Nipponica Information | Legend

1819～21年に、アメリカ合衆国でミズーリの連邦加入の際、奴隷制度をめぐって南部と北部の間に成立した協定。1803年の「ルイジアナ購入」によって得られた土地の一部分であったミズーリには、フランス領時代から奴隷制度が存在していた。当時奴隷州と自由州は同数であったが、連邦議会上院では南部、下院では北部が優勢であった。そこで下院は、19年2月ミズーリの連邦加入について、同地域の奴隷制度の漸進的廃止を条件とするニューヨーク出身のJ・タルマッジの修正案を可決したが、上院はこれを否決した。その後奴隷制度をめぐる激しい論争を経て、結局、当時マサチューセッツ州から分離して連邦加入を申請していたメーンを自由州とし、これに、ミズーリは奴隷州として認めるが、同州を除いて今後ルイジアナ購入の残りの部分では、北緯36度30分以北に奴隷州をつくらないというイリノイのJ・B・トーマスの修正案を加えることにより、20年3月に南北の妥協が成立した。

　この後、ミズーリが起草した州憲法中の、自由黒人の州内移入を禁ずる条項が連邦議会で問題となった。しかし翌年ふたたび妥協が行われ、ミズーリは、合衆国市民の権利を奪うような条項を州憲法中に設けないことを条件に、ようやく連邦に編入された。こうして南北の対立は一時的に鎮静し、メキシコ戦争のころまで奴隷州と自由州の均衡が保たれたが、「一八五〇年の妥協」を経て、54年のカンザス・ネブラスカ法で、住民主権の原則の導入によって、北緯36度30分以北に位置するカンザスが奴隷州になる可能性が生まれたことで、ミズーリ協定は無効となった。

［竹本友子］

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