The Louisiana Purchase raised questions for Americans. What peoples and land lay in the newly acquired territories? Would the rivers lead them to the Pacific Ocean? Thomas Jefferson organized a Corps of Discovery, led by Captain Meriwether Lewis and Captain William Clark, to find the answers.

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    On March 10, 1804, France officially transferred ownership of the Louisiana Territory to the United States. President Thomas Jefferson had acquired—purchased—the Louisiana Territory almost a year earlier, for the price of about $15 million (about $312.5 million, adjusted for inflation). The ceremony took place in St. Louis, Missouri, earning the city its nickname “Gateway to the West.”
    With the Louisiana Purchase, the Mississippi River, on which St. Louis sits, really did become the gateway to the west. The river formed the eastern boundary of the Louisiana Territory—a vast region stretching from the Mississippi Delta to what are now the Canadian borders of Montana and North Dakota. 
    Just months later (in May) Meriwether Lewis, William Clark, and their “Corps of Discovery” departed from St. Louis to explore this new American landscape.
  • Term Part of Speech Definition Encyclopedic Entry
    acquire Verb

    to get or take possession of.

    bank Noun

    a slope of land adjoining a body of water, or a large elevated area of the sea floor.

    border Noun

    natural or artificial line separating two pieces of land.

    Encyclopedic Entry: border
    boundary Noun

    line separating geographical areas.

    Encyclopedic Entry: boundary
    ceremony Noun

    activities to celebrate or commemorate an event.

    corps Plural Noun

    group of people acting together, or with a similar purpose.

    delta Noun

    the flat, low-lying plain that sometimes forms at the mouth of a river from deposits of sediments.

    Encyclopedic Entry: delta
    depart Verb

    to leave.

    inflation Noun

    increase in the price of goods and services.

    landscape Noun

    the geographic features of a region.

    Encyclopedic Entry: landscape
    Louisiana Purchase Noun

    (1803) land bought by the United States from France, extending from the Mississippi River to the Rocky Mountains, and Canada to the Gulf of Mexico.

    purchase Verb

    to buy.

    region Noun

    any area on Earth with one or more common characteristics. Regions are the basic units of geography.

    Encyclopedic Entry: region
    territory Noun

    land an animal, human, or government protects from intruders.

    transfer Verb

    to pass or switch from one to another.

    vast Adjective

    huge and spread out.