how significant was the Mexican war in increasing sectional tension in the USA up to 1850?

Answer 1

The result of the Mexican War was that not just Texas (already annexed, which helped to prompt the war) but a significant chunk of western territory was gained from Mexico. This immediately raised the issue of whether the new territory would end up as free states, slaves states, or some combination.

The South, already feeling pressed by the Northern POPULATION growth (which gave the non-slave section more representation in the House), was eager to gain new slave states with the added political power that would bring (to legally safeguard their 'peculiar institution') and to prevent the North from gaining "free" states that would work in the opposite direction.

Meanwhile, the "Free Soil" sentiment in the North had grown stronger, with the desire to limit or even PREVENT the spread of slavery into new territories.

Answer 2

Very significant. The south wanted us to conquer Mexico so they had the makings for several more slave states. When we didn't annex a significant part of Mexico, the south saw that the were running out of room for slave states and would soon be at a disadvantage in the Senate which had been kept equal up until that time.

Answer 3

Like someone will remember or know that!