Missouri
state rights over the issue of withdrawal from the union and the issue of slavery
the issue of slavery became important again in 1850. At that time, california requested to join the union as a free state.
Slavery was a states rights issue. The essential problem was if a state had the right to allow slavery when the federal government states it is illegal. We are still arguing the issue today. For Lincoln it was an issue of keeping the union together. Slavery wasn't so much the cause but a emotional and political response of where the power of the federal government stops and the state begins.
The Civil War caused Virginia to split into two separate states over the issue of slavery. When Virginia seceded from the Union in April 1861, the western region, which had a different economic structure and less reliance on slavery, opposed this decision. Consequently, in June 1863, the western part of Virginia was admitted to the Union as the new state of West Virginia. This split highlighted the deep divisions within the state regarding the institution of slavery.
You could be referring to Missouri in 1819/20 or California in 1850.
no massachussetts was a union state.
illinois
The Union States (northern and non slavery) and the Confederate State (seceded from the union, southern, and pro slavery).
California entered the Union as a free state on September 9, 1850. This admission was part of the Compromise of 1850, which aimed to address the contentious issue of slavery in the territories acquired from Mexico. California's entry as a free state was significant in the ongoing debates over slavery in the United States.
Slavery was the straw that broke the camel's back. It 'pushed the envelope' of the already heated issue of State's Rights- The South held State's Rights (such as choosing whether or not to allow slavery) above national unity, so they succeeded from the union.
In 1849, Californians sought statehood and, after heated debate in the U.S. Congress arising out of the slavery issue, California entered the Union as a free, nonslavery state by the Compromise of September 9, 1850.