1743

• The Verendryes, French Canadian explorers in search of the Western Sea, are believed to have sighted the Big Horn Mountains before being turned back because of fear of the Snake, or Shoshone Indians.

1763

• Spain obtains Louisiana from France.

1800

• Louisiana is returned to France.

1803

• The Louisiana Purchase from France includes three-fourths of present Wyoming.

1804-06

• Lewis and Clark Expedition goes through Montana on way to West Coast. Sacajawea, Shoshone wife of Charbonneau, guide for the expedition, accompanies him and renders invaluable service because of her knowledge of the Indians and of the country through which they pass.

1806-07

• John Colter, who came West with Lewis and Clark, is credited with being the first white man to enter present Wyoming. He discovers headwaters of Snake, Green, and Wind rivers. Because of his unbelievable accounts of the natural wonders in Northwestern Wyoming, Yellowstone National Park is called "Colter's Hell."

1807

• Ezekiel Williams leads trapping expedition into Wyoming. Williams and other members of his party are known as "the lost trappers" because of their wanderings.
• Manuel Lisa, of the Missouri Fur Co. (1807-20), hires Colter.

1807-08

• Edward Rose, a member of the Williams party, becomes the first settler in the Big Horn Basin.

1808

• John Jacob Astor, April 6, obtains a charter from the state of New York for the American Fur Co., a general title including all of his interests. He operates in the West under the name of the Pacific Fur Co.

1811

• Wilson Price Hunt's party, the first organized expedition in Wyoming, crosses the Continental Divide on its way to Astoria, Oregon. Hunt's Pass (Teton Pass) is named for him.
• Andrew Henry carries fur trade west of the Rockies.

1812

• Robert Stuart, going eastward from Astoria, may have discovered South Pass as well as the natural roadway along the Platte. He is also credited with building the first cabin in Wyoming, on Poison Spider Creek near Bessemer Bend.

1819

• Florida Treaty gives Spain's claim to Oregon to the United States.

1820

• Mexico secedes from Spain.

1820-21

• The approximate date Jacques LaRamie, trapper, is supposed to have been killed by Indians. Landmarks in Southeastern Wyoming perpetuate his name.

1822

• The Ashley-Henry Fur Co., later known as the Rocky Mountain Fur Co., is organized.
• Jim Bridger— trapper, trader, and teller of tall tales—comes West with the Ashley Expedition.

1824

• Ashley's men, headed by Thomas Fitzpatrick and Jedidiah Smith, cross mountains at South Pass and are credited with naming the Sweetwater and changing the name of the Spanish River to Green River, honoring one of his St. Louis partners. Ashley's men gather at the Three Crossings of the Sweetwater. This is a forerunner of the rendezvous.
• Mexico acquires independence from Spain.

1825

• Ashley and his men, descending the Green River, are the first to navigate the stream.
• First official rendezvous is held on Henry's Fork on Green River near Wyoming-Colorado border. Notices are posted ahead of time.
• Ashley takes cargo of furs to St. Louis via Big Horn, Yellowstone, and Missouri rivers. On his return he follows land route and proves that it is more practical than going by water.

1826

• Rendezvous is held in Cache Valley (Weber River, Utah) . There, Ashley turns his interests over to Jedidiah Smith, William Sublette, and David Jackson, who reorganize the Rocky Mountain Fur Co. (1826-36).

1827

• Smith, Jackson, and Sublette bring the first wheeled vehicle, a four-pound cannon, across South Pass on the way to rendezvous held at Bear Lake, near the Idaho-Utah line.

1828

• Partuguese Houses, a forerunner of trading posts, are established on the Middle Fork of Powder River.
• Rendezvous is held at Bear Lake.

1829

• First wagons ever brought to Wyoming take supplies to rendezvous on the Popo Agie, tributary of Wind River.
• A second rendezvous is held at Pierre's Hole (Idaho).
• The mighty American Fur Co. (1829-45) is organized by Astor on an operating basis.

1830

• Rendezvous is held on Wind River, thirty miles above mouth of Popo Agie. Smith, Jackson, and Sublette bring wagons loaded with supplies.

1831

• Rendezvous is held at Cache Valley. Another is held during the winter (1831-32) on the South Fork of Powder River.

1832

• Captain B.L.E. Bonneville takes first wagon train through South Pass on way to the rendezvous at Pierre's Hole, Idaho. It consists of twenty-eight wagons, loaded with provisions.
• Bonneville establishes Fort Bonneville, a temporary post on Horse Creek, a tributary of Green River. It is so impractical it lasts only one month and is known as "Fort Nonsense" or "Bonneville's Folly."
• The captain notes presence of oil in Popo Agie region.
• Nathaniel Wyeth enters the fur trade.

1833

• Rendezvous is held on Horse Creek, near site of Fort Bonneville, six miles west of present Daniel, Wyo.

1834

• Fort William on the Laramie River (later Fort Laramie ) becomes the first permanent settlement in Wyoming. Its founders are Robert Campbell and William Sublette, for whom the post is named.
• Jason and Daniel Lee, first missionaries, come West with Wyeth.
• Rendezvous is held at Ham's Fork.

1835

• Fort William is sold to Fitzpatrick, Milton G. Sublette, and Bridger.
• Rev. Samuel Parker, near present Bondurant, conducts first Protestant service ever to be held in Wyoming.
• Parker and Marcus Whitman attend rendezvous at Horse Creek on Green River. Attendance is estimated at two thousand Indians and two hundred whites.
• Whitman removes arrow from Bridger's back.

1836

• Fitzpatrick, Sublette, and Bridger sell interests to the American Fur Eliza Spalding (Mrs. H. H.) and Narcissa Whitman (Mrs. Marcus), the first white women to follow the Oregon Trail through Wyoming, accompany their missionary husbands. They impress Indians at rendezvous, held on Green River near Daniel.
• Mrs. Susan B. Luman, born at Fort William, 1836, is said to be the first white child born in Wyoming.

1837

• Rendezvous is again held on Green River, this time twelve miles south of Horse Creek. Popularity of the rendezvous system is indicated by presence of about three thousand Indians.

1838

• Rendezvous on the Popo Agie, at the confluence with Wind River, shows decline in fur trade.
• Jim Baker, noted trapper and guide, joins the American Fur Co. and becomes permanent resident in Wyoming.

1839

• Rendezvous is again held on Horse Creek, near Fort Bonneville. Little activity.

1840

• Final rendezvous, held on the Sisk-ke-dee (Prairie Hen, the Indian name for Green River), brings end to rendezvous period.
• Father Pierre Jean DeSmet celebrates first Mass in Wyoming, near present Daniel, Wyoming.

1841

• Dr. Elijah White is first U.S. official sent to Oregon.
• Only eighty travelers are believed to have followed the course of the Oregon Trail.
• Fort William, now badly in need of repair, is rebuilt. The new, adobe-walled structure costing $10,000, is named Fort John, presumably for John Sarpy, a stockholder of the American Fur Co. The name Fort Laramie, which proves more popular than Fort William or Fort John, is attributed to the mistake of a shipping clerk.

1842

• John C. Fremont, "The Pathfinder," maps the trail and selects sites for military posts in anticipation of territorial acquisition on the West Coast.
• Elijah White leads large party of missionaries and settlers across Wyoming.
• Gold is discovered near South Pass.
• Fort Bridger, the second permanent settlement in Wyoming, is established on Black's Fork.

1843

• Fort Bridger is opened for trade by Jim Bridger and his partner, Louis Vasquez.
• Fremont's second expedition crosses Laramie Plains.
• Approximately one thousand follow the trail along the Platte. Emigrants take domestic animals.

1844

• Fremont report is issued by Congress.

1845

• Texas is annexed to the United States.
• Colonel Stephen W. Kearny and his dragoons march from Fort Leavenworth to Fort Laramie to impress the Indians, who are awed by the "cannon that talks."
• Kearny sends part of his command to explore the Sweetwater.
• Three thousand people follow the Oregon Trail.

1846

• Oregon is won by means of settlement.
• President Polk approves act to establish military posts along the trail.
• Francis Parkman visits Fort Laramie and studies habits of the Sioux.

1847

• July 4th celebration is held at "Independence Rock," which DeSmet previously called "The Register of the Desert."
• Brigham Young leads first group of Mormons to Utah. His followers cause the route to be called the Mormon Trail.
• Mormons improve roads and establish ferries.
• First sheep are driven across Wyoming.

1848

• Mexico's boundary line is established, and lands north of the border are ceded to the United States.
• Gold, discovered at Sutter's Mill (California), stimulates travel on the emigrant trail.

1849

• Fort Laramie, purchased by the government for $4,000, becomes a military post (1849-90).
• The '49ers pass feverishly through Wyoming in their quest for gold.
• Captain Howard Stansbury makes a reconnaissance for railroad route from Salt Lake to Fort Bridger.

1850

• High tide of migration is reached. Sixty thousand emigrants and ninety thousand animals, it is estimated, follow the trail in one season.

1851

• First mail route to Salt Lake is established by Hockaday and Liggett.
• Stansbury completes reconnaissance for railway route.
• The El Paso, the first steamship in Wyoming, sails up the Platte to Guernsey.
• The Great Treaty Council, scheduled to be held September 1 at Fort Laramie, is moved to Horse Creek, in Nebraska, because of scarcity of grass. The ten thousand Indians in attendance have a corresponding number of horses. As a result of the move, the Fort Laramie Treaty of 1851 is referred to as the Horse Creek Treaty.
• By treaty, the Sioux are given lands north of the North Platte River; the Cheyenne and Arapaho, "between the rivers" (North Platte and Arkansas); the Crows, from Powder River to Wind River. No lands are assigned the Shoshones, guests at the council, as they belong in the Utah, rather than the Upper Platte Agency.

1852

• William Vaux, post chaplain, teaches first school in Wyoming, at Fort Laramie.
• Forty to fifty thousand travelers follow the emigrant trail.

1853

• Fort Supply (1853-57), first agricultural settlement in Wyoming, is established by the Mormons near Fort Bridger.

1854

• Lieutenant L. Grattan and his command are killed by Indians, August 19, near Fort Laramie.

1855

• General W. S. Harney leads military expedition against the Sioux.

1856

• Mormon "Handcart Brigade" meets disaster in blizzard near Devil's Gate.

1857

• Colonel Albert S. Johnston leads Utah Expedition against Mormons in what is commonly called the Mormon War.
• The Mormons, with five mail stations between Fort Laramie and Salt Lake City, set fire to them as they retreat westward.
• The army takes over Fort Bridger, which had been occupied by the Mormons, and establishes Camp Scott as winter quarters.
• Russell, Majors, and Waddell, who previously freighted between the Missouri and Santa Fe, start freighting business through Wyoming by transporting supplies for Johnston's Army.
• Colonel E. V. Sumner leads troops against the Cheyenne Indians.
• Lieutenant G. K. Warren, topographical engineer, explores the area from Fort Laramie into the Black Hills in Northeastern Wyoming.
• Lander Cut-off, through Shoshone country, is surveyed by Colonel F. W. Lander.

1858

• Fort Bridger becomes a military post (1858-1890).

1858-59

• Russell, Majors & Waddell transport more than 16 million pounds of freight through Wyoming to Utah.

1859

• The Overland Express Company is established by Russell, Majors & Waddell, and the emigrant route acquires another name—the Overland Trail.
• Captain W. F. Raynolds is sent on exploring expedition into Northern Wyoming.
• Fort Bridger becomes a military installation.
• September 18, the Deer Creek, unofficial council is held with the Sioux, Cheyenne, and Arapaho.

1860

• The Pony Express, eighteen months in duration, crosses Wyoming on the emigrant trail.
• The second school in Wyoming is established, at Fort Bridger.
• September 10, four Arapaho and two Cheyenne sign agreement relinquishing "the lands between the rivers" for the Sand Creek Reservation in Colorado. Other Cheyenne refuse to recognize this preliminary Fort Wise Treaty, made at Bent's Fort (Colorado) in September.

1861

• In the Fort Wise Treaty, effective February 18, the Northern Cheyenne and Arapaho lose their right to Wyoming lands.
• Edward Creighton completes transcontinental telegraph line (the Overland Telegraph) across Wyoming, along the old emigrant trail.
• After the Civil War breaks out, troops are withdrawn and Indian attacks increase.

1862

• Ben Holladay, "Stagecoach King," takes over equipment of Russell, Majors & Waddell.
• Indian troubles cause the Overland Stage to be rerouted southward through Julesburg, Colorado, toward Denver, then northward on the Cherokee Trail, and over the Laramie Plains. It avoids the Sioux along the Platte but goes through Arapaho country in the Medicine Bow area.
• The Overland Telegraph along the Platte continues to be used even after another line is built along the southern route.
• The Federal Homestead Act (12 Stat. 413) is passed, June 2.
• The first legal water right is granted to Meyers Land and Livestock Co.
• Fort Halleck (1862-66) is established on the Overland Stage route.

1863

• The Bozeman Road, disregarding Indian rights, is established through the Powder River country as shortcut to Montana gold fields.
• First newspaper in Wyoming, the Daily Telegraph, is published briefly by Hiram Brundage at Fort Bridger.
• The first known export of minerals from the area is a cargo of soda shipped to Salt Lake City. Trona (native soda) deposits west of Casper give rise to the name of Natrona County.
• General P. E. Connor is sent to Wyoming to suppress Indian hostilities.
• Shoshone Lake is discovered by the DeLacey prospecting expedition.
• First Treaty of Fort Bridger, signed by Shoshone Indians, recognizes their aboriginal domain as extending from the North Platte to Salt Lake, northward into southern Montana and southward into Utah and Colorado. Roughly it comprises 44,672,000 acres.

1864

• Bozeman Road arouses hostility of the Sioux and their allies, the Cheyenne and Arapaho. The Sand Creek Massacre in Colorado, November 29, unites the three tribes.

1865

• January 5, first proposal is made for the Territory of Wyoming. The name Wyoming, "Maugh-wau-wa-ma,” derived from a Delaware Indian term, is said to mean: "at the big flats" or "the large plains."
• Survivors, fleeing from Sand Creek, smoke the war pipe with the northern bands at a grand encampment in Northeastern Colorado.
• The "Bloody Year on the Plains," results. Beginning at Julesburg in January, the Indians destroy everything in their path as they sweep northward into Wyoming.
• Lieutenant Caspar W. Collins, for whom Fort Caspar and Casper, Wyo., are named, is killed by Indians at the Battle of Platte Bridge (July 25) , the major engagement of the year. The military order establishing the post incorrectly designates it as Fort Casper.
• General P. E. Connor, with Jim Bridger as guide, leads first Powder River Expedition and establishes Camp Connor, August 28. The name is changed to Fort Reno, November 11. On August 29,
• Connor destroys 250 lodges of Arapaho under Black Bear at Tongue River. Colonel N. Cole and Lieutenant Colonel Samuel Walker, commanding two columns under General Connor, become lost; and they and their eighteen hundred cavalrymen are in starving condition when found. During a severe storm their horses die by the hundreds in the picket lines. The surviving six hundred horses are unfit for service. As a result, Connor is relieved of his command.
• General Grenville M. Dodge and troops camp on Crow Creek while investigating feasibility of railroad route over Laramie Mountains.

1866

• Red Cloud walks out of peace council held with Sioux, June 5, at Fort Laramie.
• Over Indian protest, Fort Reno (originally Camp Connor), Fort Phil Kearny, and a third post (Fort C. F. Smith in Montana) are constructed on the Bozeman Road. Fort Phil Kearny, "the hated fort on the Little Piney," is under constant attack.
• Nelson Story drives the first herd of cattle through Wyoming on way to Montana from Texas.
• Fort Sanders (1866-82) is established on the southern Overland Stage route.
• The first book believed to be published in Wyoming is the Dictionary of The Sioux Language. About 50 copies are printed on a small army press.
• On December 21, Captain William J. Fetterman and eighty men are ambushed and killed by Indians near Fort Phil Kearny. John "Portugee" Phillips rides to the Horseshoe Telegraph Station and on to Fort Laramie to report the Fetterman Massacre and request reinforcements for the beleaguered fort.