How and why real property interests came about:

Real property interests are typically understood to include both the surface and subsurface, or mineral, estates. For those of us involved in the purchase and sale of ranch real estate in the American West, the surface and mineral estates are key components of any transaction.

The “American West” includes the 21 “federal states”, with the exception of Texas, Hawaii, and Alaska, west of the Mississippi River. The Federal government annexed these lands in a series of foundational treaties: the 1803 Louisiana Purchase from France (503 million acres or 786,000 sq miles), the 1848 Hidalgo Treaty with Mexico (339 million acres or 530,000 sq miles) and the 1848 Oregon Treaty with Britain (191 million acres or 298,000 sq miles) displayed in Figure 1 below.