Tons of Americans decided to head west and expand. Their were many different reasons for westward expansion such as gold, new land, animals and trade, new jobs, and a new start.
People who moved out west for the gold rush clearly came for the gold. The gold rush started in Sacramento Valley in early 1848 which sparked the Gold Rush. This is one of the most significant events to shape American history during the first half of the 19th century.
Even though many of Americans expanded west for gold not all were successful. Many came and didn't find anything, or along the journey west they got sick, and even died. They had a huge impact because they made many new small towns and gave them tons of business. With so many people expanding the population grew in the west quick.