After the discovery, thousands of gold-seekers flooded into the area. As a result, California drafted a constitution and then applied for statehood, thus bypassing the usual territorial stage and avoiding becoming a slave state. This, of course, caused fighting between the North and South as to whether the state should be admitted as a slave state or free state. This event was higher up on the list because it was the first large event to bring sectionalism back to America. However, it was not nearly as important as some of the events that followed this annexation.
6. The Kansas-Nebraska Act was the act which would let slavery in Kansas be decided by popular sovereignty. The act itself conflicted heavily with the Missouri compromise and wrecked the Compromises of 1820 and 1850. Because of this, Northerners no longer enforced the Fugitive Slave Law at all and Southerners were still angry about the act itself. Because both sides became inflamed by the act, it warrants being number 5 on the list.
5. The Lecomption Constitution and the establishment of Kansas as a slave state warrants being the next-most important event of this list. The Lecompton Constitution, which provided that the people were only allowed to vote for the constitution of Kansas "with slavery" or "without slavery". If elected "without slavery", then those slaveholders already I the state would still be protected. Thus, on election day, free soilers boycotted polls and Kansas approved the constitution with slavery. Northerners were inflamed by this and tension increased greatly. Also, the Democratic Party became helplessly divided by this decision, ending the last remaining national party for years to come. Therefore, it is reasonable to consider this act as being the fifth-most important event to happen.
4. The Compromise of 1850 was a huge factor that spurned the Civil War. The northerners got the better deal, and California was admitted as a free state.