Timeline: Missouri Compromise
1803
President Thomas Jefferson (Democratic-Republican, 1801-09)
brokers the Louisiana Purchase—a deal with French Emperor
Napoleon Bonaparte to purchase more than 530 million acres
of land west of the Mississippi River. The Louisiana Purchase
effectively doubles the size of the U.S.
1818
In January, Congress receives the first of many petitions for
statehood for Missouri, a federal territory constituting part of the
Louisiana Purchase.
1819
On February 13, the Missouri Bill, authorizing Missourians to
form a constitution and state government, is introduced in
Congress. In response to Missouri's desire to enter as a slave
state, antislavery Representative James Tallmadge
(Democratic-Republican, New York) on February 13 proposes
two major revisions to the bill that would lead to the gradual
emancipation of slaves in Missouri. The Tallmadge Amendment
sets off a firestorm of controversy along sectional (North-South)
lines; it narrowly passes the House but fails in the Senate.
Still deadlocked on the Tallmadge Amendment, the last session
of the 15th Congress adjourns in March without admitting
Missouri.
In December, the District of Maine, which had been a part of
Massachusetts, petitions to enter the Union as a free state.
Speaker of the House Henry Clay (DR, Kentucky) warns that
the South will attempt to bar Maine's entry unless Missouri is
admitted as a slave state.
On December 14, Alabama enters the Union as the 22nd state.
Its admission as a slave state brings the total number of slave
states to 11—the same as the number of free states.
1820
On February 17, the Senate passes an amendment submitted
by Senator Jesse B. Thomas (DR, Illinois). Also known as the
Missouri Compromise measure, the Thomas Amendment
proposes a permanent ban on slavery in the remaining territory
of the Louisiana Purchase north of 36°30' latitude and west of
the Mississippi River.
On February 19, the Senate approves the Maine statehood bill,
which it had merged with the Missouri Bill three days earlier.
The House rejects the so-called Maine-Missouri bill, and
refuses to consider legislation linking Maine and Missouri. In
the face of deadlock, in a House-Senate conference committee,
the Senate agrees to consider Maine and Missouri separately
and the House agrees to stop trying to prevent slavery in
Missouri.
The House on March 2 votes to allow slavery in Missouri and
also approves the inclusion of the Thomas Amendment in the
Missouri Bill.
The Missouri Compromise is officially approved on March 3. In
a separate action that day, Maine's admission as a free state is
approved.
On March 6, the Missouri Enabling Act, "An Act to authorize the
people of the Missouri territory to form a constitution and state
government, and for the admission of such state into the Union
on an equal footing with the original states, and to prohibit
slavery in certain territories," is signed into law.
On March 15, Maine is admitted to the Union as the 23rd state.
1821
In the so-called Second Missouri Compromise on March 2,
Congress agrees to admit Missouri into the Union only if the
Missouri legislature revises its state constitution to allow entry
to free African Americans. The Missouri legislature consents to
the provision in June.
On August 10, Missouri is admitted to the Union as the 24th
state.
1857
The Missouri Compromise is declared unconstitutional by the
Supreme Court, in Dred Scott v. Sandford.
1865
The 13th Amendment is ratified on December 6, abolishing
slavery in the U.S.
Citation Information
MLA Chicago Manual of Style
“Missouri Compromise - Timeline.” Issues & Controversies in American History. Infobase Publishing, 13 Dec.
2006. Web. 25 Oct. 2013. <http://icah.infobaselearning.com/icahtimeline.aspx?ID=112070>.