The major events in the Kansas controversy can be easily defined. Over the period from the passage of the Kansas-Nebraska Act in May 1854 to late 1856, a mini-civil war took place in Kansas, with an illigitimately elected pro-slavery government, pro-slavery settlers and Border Ruffians from Missouri fighting in sporadic guerrilla warfare, and sometimes in regular military engagements, with the Free States settlerls.
It is this period in particular that is remembered as "Bleeding Kansas". (The title of the linked article says "Bleeding Kansas 1853-1861", but the text makes it clear that 1854-6 was the key period of violence.) Although Kansas remained a point of contention between North and South up until the Civil War began in 1861, the Free State forces had clearly gained the upper hand by 1857, despite pro-slavery administrations in Washington. Kansas was admitted to the Union as a free state in 1861 after the Confederate states seceeded.
The historical and political significance of events can't be easily quantified. But some numbers will help put the Kansas conflict into some context. First of all, something like 55 people are said to have lost their lives in the 1854-6 conflict there. Since it's not unusual these days to hear about that many people or more being killed in the combined insurgency and civil war in Iraq, it would be easy for present-day readers to brush the Kansas conflict off as an insignificant set of skirmishes. Particularly when the "butcher's bill" for the Civil War came in at over 600,000 dead.
But this was 1854, and the armed rebellion of the Slave Power was still years ahead in an uncertain future.
The Howard Committee Report provides several tables that give us some valuable figures. In a table showing the number of votes on November 29, 1854, showed the number of eligible voters at 2,905. The settlements in Kansas were clustered near the Missouri border, which made it convenient for the Border Ruffians from that slave state to interfere in Kansas affairs, as they surely did. That same table shows that 1,114 legal voters participating in the election, along with 1,729 illegal ones, probably all from Missouri.
Immigration was active at this time. So by January-February of 1855, as a subsequent table shows, a total of 8,601 settlers were in Kansas, of which 3,383 were female, 3,469 were children and 192 were slaves. To do a gruesome piece of math to put things in perspective, if we think of present-day Iraq levels of civil war deaths at 50 a day or so, with a population of 9,000 in February of 1855, a number equal to the entire population of Kansas would have been wiped out by the end of August, 1855.
The political significance of the Kansas events can't be measured in absolute numbers of casualties. One final example for comparison. It's not unusual for large American cities to have 55 murders in a year from family fights or crime. But, for all the venom in American politics, how many people have been killed lately in partisan political shootouts in the United States? And think about California, with upwards of 30 million people, and imagine that there had been 55 partisan political killings in violent clashes in the last two years. It would be regarded as a terrifying trend.
So with a few thousand people in Kansas in 1854-6, that level of violence seemed like intense conflict. And the partisans of both sides in the rest of the country regarded it so, as well.
With that for context, the major events of 1854-6 in Kansas can be summarized as follows. The first election in November, 1854, is stolen by the Missouri Border Ruffians. The same happens with the elections in March, 1855, known as the "Shawnee Mission" government and then in 1856 and thereafter as the "Lecompton" government. The pro-slavery legislature then passes draconian laws against any sort of abolitionist activity. The Free State partisans organized their own state government in the fall of 1855, known as the "Topeka" government but whose real stronghold was Lawrence. In November, 1855, an armed group of 1,500 pro-slavery men surrounded Lawrence, where about 500 Free State men prepared to give battle. A peace agreement, known rather grandly as the "Wakarusa treaty", averted the clash, which was even more grandly called the Wakarusa War.
In March, 1856, the Free State legislature met in Topeka and petitioned Congress to admit Kansas as a free state. The pro-slavery government moved against the Topeka government by another attack on Lawrence on May 21. The Topeka forces decided not to fight at that point, and the "sack of Lawrence" occurred. As coincidence would have it, on Thursday, May 22, the thuggish Southern gentleman Preston Brooks assaulted Massachusetts Senator Charles Sumner in the Senate with a cane and beat him badly after Sumner had given a fiery speech about the conduct of the pro-slavery forces and the Franklin Pierce administration in Kansas. That weekend, the Kansas conflict was intensified when a small group headed by John Brown killed five pro-slavery settlers, in what would be known as the Pottawatomie massacre.
More clashes followed. In the Battle of Black Jack in early June, Brown's band captured a much larger band of Missouri Border Ruffian militia. Another Missouri invasion followed in August, and they defeated Free State fighters, again including John Brown, at Osawatomie. Brown was nevertheless regarded as a hero in that battle, and was nicknamed "Osawatomie Brown". In September, John Geary arrived as the new governor of the territory. He soon succeeded in discouraging the guerrilla fighters on both sides, assisted by the US Army which intervened with 2,700 troops to prevent another attack on Lawrence by the Lecomptom partisans that same month. The territory calmed down after that. Neither the political conflict nor the violence was over, but it's most intense period was done.
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