Final answer:
The Federalists were upset about the Louisiana Purchase because they were concerned that it would lead to the creation of more states that aligned with the Democratic Republicans, thus diminishing their own influence.
Step-by-step explanation:
The reason the Federalists were upset about the Louisiana Purchase was that they were concerned that more states would become Republican. The Democratic Republicans, led by Thomas Jefferson, supported the purchase and saw it as an opportunity to expand their political power in the new territories. The Federalists, who opposed Jefferson and his party, feared that the acquisition of more land would lead to the creation of more states that would align with the Democratic Republicans, thus diminishing their own influence.
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