The region aded from 1803 to 1819 to US were:
-in 1803: Louisiana
-in 1810: West Florida
-in 1818: Red River
-in 1819: East Florida
From 1803 to 1819, the United States added several key regions including the Louisiana Territory, West Florida, the Red River Territory, and East Florida. These acquisitions were primarily achieved through purchases and treaties. This expansion played a crucial role in the growth of the nation during its early years.
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