Briefly explain how one specific historical event or development during the period 1865 to 1898 that is not explicitly mentioned in the excerpts could be used to support turner's interpretation.

Frederick Jackson Turner wrote his thesis (The Turner Thesis) and presented it at the 1893 World's Fair. The main point of the thesis was that the US was shaped by the expansion westward and now was closed therefore the formation of the American ideal was also complete. 

Evidence to support his thesis is:
--Final battles with Native Americans on the Plains and west coast. Beginning the official reservation period. 

--Completion of the trans-continental railroad

--Land acquisition from 'sea to sea' complete. 

--All land that will become states (including Alaska and Hawaii) are under the control of the US government. 

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