United States Timeline
1785 The Northwest Ordinance was the first of over 300 laws passed by the federal government to help encourage settlement, to survey the land, and to establish a legal record-keeping system. The rectangular survey system was established dividing most of the land in the public domain into townships and sections.
1803 The Louisiana Purchase: 885,000 square miles of land between the Mississippi River and the Rocky Mountains that the United States purchased from France.
1812 The United States annexed portions of West Florida to Louisiana and to the Mississippi Territory.
1819 Spain ceded the remainder of West Florida and all of East Florida to the United States.
1846-1848 The Mexican War was fought between the United States and Mexico over U.S. expansion. At the end of the war, a treaty gave the United States land extending from Oklahoma to California.
1862 Homestead Act: Land was distributed after 1862 to homesteaders who could receive a patent (title) to the land by residing on it and making improvements for five years. Subsequent laws modified the requirements and the amount of land one could obtain by homesteading.