I'm not sure what specifically you're referring to when talking about what changed in 1926 so here's a resource for you that has a bit of information about what was going on in 1926.
http://www.thepeoplehistory.com/1926.html
<span>The revolt of Gabriel Denmark Vessey and Nat Turner influenced the northern abolitionist movement by passing laws to restrict the slave trade. Many slaves led revolts during this time on plantations to abolish slavery. Unfortunately, many captured slaves were executed.</span>
Wanted a chief exective who would be a diplomat among world leaders