They built 11 mounds at Spiro near the Arkansas River.
The factor that benefited the Republican Party in the 1970s was: <span>reaction by some white southerners to passage of civil rights laws
Back then, the southerners still haven't supported the equal civil rights laws for the minority citizens. This massively decreased Kennedy's support that became the Republican main opposition during that time.</span>
President Jackson started "the spoil system' of hiring people and created "kitchen cabinet" by keeping his loyalists close to him.
<h3>Which system was started by the president Jackson?</h3>
The spoil system is that system, in which a political party rewards the workers and supporters to the post of the government.
He created a Kitchen cabinet. in which he kept his loyalists like newspaper editors, journalists etc. in order to support his ideas of the spoil system.
A great support was provided by his loyalist in the implementation of the Jackson's system.
Learn more about the spoil system here:-
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The name is Pre-Cambrian era