From the perspective of the US the Louisiana Purchase was significant because utilizing the Mississippi river would be great for agriculture. From the perspective of the French, the Louisiana purchase was significant because they stopped future conflicts with the United States, and they will not have to rule a land that is very far away from them.
The Mexican War
Ok but we will get all of the land
If it will stop conflicts between Mexico and the United States, we will surrender from war
From the perspective of the Cherokee the Indian Removal Act was significant because they will have to build a whole new way of life to survive on new grounds. From the perspective of the Americans the Indian Removal Act was significant because White settlers would gain more land.
Oregon Treaty
1820-1840's
Oregon Treaty We are moving the Native Americans Westward
That's a good idea
Our tribes should make an alliance with each other
From the perspective of the Mexicans, Texas independence was significant because it would ultimately trigger the Mexican war, which was a major impact on the Mexicans. From the perspective of the United States, Texas independence was significant because Texas would add a lot of land to their country.
The Gold Rush
1849
1840's
I'm ready for war!
From the perspective of the Americans the Mexican war was significant because they were able to make plans for the new territory they gained. From the perspective of the Mexicans, they Mexican war was significant because the loss of Texas actually stopped the fighting and conflict between the US and Mexico.
1840 - 1850's
From the Perspective of the Americans the Oregon treaty was significant because the United States would now stretch from coast to coast. From the perspective of the Native Americans the Oregon treaty was significant because this caused tribes to join together.
1846
Yay! we get the land
Yeah, we have the best country
From the perspective of the Sioux, the conflict in the west was significant because it would lead the battle at little big horn. From the perspective of the Americans the conflict in the west was significant because they not only gained land, but they also gained gold as well.