Receiving education in the U.S. it always seemed to be a major event in U.S. history courses but world history courses rarely if ever mentioned slavery outside of one in college.
You may be interested in my earlier answer on slavery and its abolishment in Mexico, in the early 19th century shortly after independence (see esp. the second part on abolition).
At least two things to keep in mind here: African slavery had already lost importance before then due to various differences in Latin America (viz British America) that I outline. And that abolition came under Vicente Guerrero, the first president of African descent in North America - the wars for dependence in Mexico had especially high participation of indigenous, African and mixed peoples, even as leaders.
Hope this helps!