Students study political maps of the territories that went on to form the current state of Montana. They learn the impact of treaties, government policies, and conflicts on borders.
This lesson is part of "Great States: Montana | Unit 7: Conflict" where students will learn about how building tensions led to violent combat between Montana’s American Indians and the US government.
3.2: Locate on a map or globe physical features (e.g., continents, oceans, mountain ranges, landforms) natural features (e.g., flora, fauna) and human features (e.g., cities, states, national borders).
3.5: Use appropriate geographic resources (e.g., atlases, databases, charts, grid systems, technology, graphs, maps) to gather information about local communities, reservations, Montana, the United States, and the world.
Helena District 3.5: Use maps, atlases, graphs, and charts to gather and interpret information about Montana, including Montana Indian reservations.
- Map: Louisiana Purchase 1803/Missouri Territory 1812
- Map: Dakota Territory 1861
- Map: Idaho Territory 1863
- Map: Montana Territory 1864
- An interactive whiteboard, projector, or another type of screen to show images to the class
- Class set of the Changing Borders of America handout
- Different colored markers or colored pencils
Pass out handout of current US map (with lightened/very transparent current state lines) and have students draw lines and mark each step in the history of the United States’ 19th-century land acquisition, based on the provided maps.
Distribute the Changing Border of America handout. This handout has a current US map for reference and questions for students to answer as you make your way through showing the map series.
Show students the first map of the series, Louisiana Purchase 1803 / Missouri Territory 1812, and explain that Thomas Jefferson purchased the lands west of the Mississippi River from the French in 1803 (highlighted in orange). It was one of the biggest land deals in history.
Clarify for students that in 1812, Louisiana became a state after the United States claimed the rest of the state’s land from Spain (1812 state boundaries have been outlined), and the rest of the Louisiana Purchase’s land (north of the Louisiana state lines) was renamed the Missouri Territory.
Tell students that after Minnesota became a state in 1858, the land between Minnesota and the Missouri River became disorganized. The land was restructured as the Dakota Territory, with the help of Abraham Lincoln’s cousin-in-law and newly-appointed Dakota Territory Delegate, J.B.S. Todd.
Next, show students the third map of the series—Idaho Territory 1863. Explain that Congress and President Abraham Lincoln created the Idaho Territory in 1863 to span the land across either side of the Great Continental Divide. Tell students how the Great Continental Divide is a mostly mountainous line that divides water in different directions. South of Glacier National Park, the Great Continental Divide separates water into two directions: to the west of the divide, water flows down rivers, streams, and tributaries out to the Pacific Ocean, whereas to the east, all water moves to rivers and basins that lead toward the Atlantic Ocean and the Gulf of Mexico. The land west of the Great Continental Divide combined with part of the Washington Territory to become the Idaho Territory.
Lastly, show the fourth map of the series, Montana Territory 1864. President Abraham Lincoln determined the current borders of Montana to form a new territory in 1864. Montana later became a state on November 8, 1889.
Iowa, Missouri, Arkansas, Louisiana, Oklahoma, Kansas, Nebraska, South Dakota, (part of:) North Dakota, Montana, Wyoming, Colorado, Texas, Minnesota
Montana, Wyoming, North and South Dakota, and a small bit of Nebraska
Idaho, Montana, and Wyoming
The Continental Divide
The Atlantic Ocean/Gulf of Mexico