Explanation:
The main reason for this was slavery. The US did not want to annex Texas because doing so would have upset the balance between slave states and free states that had been accomplished with the Missouri Compromise of 1820. When Texas became independent, it wanted to join up with the United States.
<span>B Because the Soviets were instilling communist governments in many countries
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Two most important factors were the development of industry and industrialization, and the slave trade. People started accumulating large amounts of wealth due to these two and started investing them in businesses, both personal and by other people. This led to the development of capitalism not only in Europe, but other places too.
Your question is rather vague by just giving dates ... but I think I know what you might be looking for here. During the "antebellum" (before the Civil War) years and again in the years after the Civil War, there were strong movements by social activists that went against how society wanted to keep women and African Americans in "their place." Social reformers thought that the place assigned to women or to blacks was not at all right. They put forward better ideas of how black Americans and female citizens should have equal status with whites and with men in regard to political, social, and economic rights.
The activist movements from 1820 to 1848 and again from 1865 to 1898 didn't achieve all their goals in that time period, but they began to advance the causes of civil rights for blacks and women -- both movements which would continue into the 20th century.