Pony Express By RubySale Period: Sep 1, 1847 to Mar 31, 1849 Events Leading To Pony Express Jan 1, 1848 Gold is discovered in California and thousands of settlers head west. Gold is discovered in California and thousands of settlers head west. Jul 1, 1859 Gold discoveries in Colorado and Nevada bring more settlers to the west. Period: Jul 1, 1859 to Dec 31, 1861 Pony Express Oct 26, 1861 Pony Express exchanged for telegraph lines bringing the Pony Express to a halt.