What conditions influenced the United States expanation abroad

5 answers

What is expanation?

To what time period are you referring?
Sorry I ment expansion abroad. (Westward expansion )
The 19th century
I wouldn't call the Westward Expansion expansion abroad. This implies over the ocean -- but our westward expansion was over land.

The conditions that influenced it:
lots of land
many new immigrants
desire of easterners to buy cheap land

Most of my ancestors moved from near the east coast to the midwest to buy good, inexpensive farmland.
Also consider the California Gold Rush and other mineral/mining "rushes" such as the Comstock Lode, the Alaska (Klondike) Gold Rush in the 1890s, etc.