This region that was hunted by American Indians for many generations is claimed, as part of the Mississippi River drainage, for France by Robert Cavelier de La Salle, and called Louisiana.

Brothers Francois and Louis-Joseph La Verendrye, with two other Frenchmen, are the first known white men to explore the Little Missouri badlands of present-day North Dakota.

France cedes Louisiana to Spain.

Spain cedes Louisiana back to France.

France sells Louisiana to the United States.

Trapper Jean Baptiste La Page descends the Little Missouri River and soon joins Lewis and Clark in their winter camp on the Missouri.

Area becomes part of Louisiana Territory.

Area becomes part of Missouri Territory.

Area becomes unorganized territory.

John Palliser, a British adventurer, hunts bear along the Little Missouri, and in 1853 publishes Solitary Rambles and Adventures of a Hunter in the Prairies.

Area becomes part of Nebraska Territory.

Sir St. George Gore, an Irish sportsman, leads a large hunting expedition along the Little Missouri.

Area becomes part of Dakota Territory.

General Alfred Sully leads 2, 200 army troops and a civilian wagon train across the badlands just south of present-day Medora. They fight a large force of Lakota and Dakota Sioux in the "Battle of the Badlands" on August 7-9. Among the Indians is Fanny Kelly, a captive white woman, who in 1871 publishes Narrative of My Captivity Among the Sioux Indians.

Pierre Jean De Smet, a Jesuit missionary, and his escort travel through the badlands to Montana to meet with Sitting Bull's band of Hunkpapa Lakota, and return by the same route.

Railroad survey crew and military escort pass through the badlands near present-day Medora.

Another railroad survey crew and military escort pass through the area.

A third railroad survey crew and military escort, including General George Custer and his Seventh Cavalry, pass through the area.

A military expedition, including Lieutenant Colonel Custer and his Seventh Cavalry, pass through the area on their way to Montana. Custer and more than 200 of his men die at the Little Bighorn on June 25. General George Crook leads his men through from Montana in September.

Billings County is created on February 10, but remains unorganized. The first range cattle enter the area. U. S. Military establishes Badlands Cantonment on the west side of the Little Missouri on November 10, to protect railroad construction crews from Indian attack.

A small town called Little Missouri builds up between Badlands Cantonment and the river. Northern Pacific railroad reaches Little Missouri in the fall, opening the area to hunters, naturalists, and tourists. More cattle ranches begin to operate along the river.

Badlands Cantonment is abandoned on March 4. 24 year old French nobleman Antoine-Amedee-Marie-Vincent-Amat Manca de Vallombrosa, the Marquis de Mores, founds the town of Medora east of the river on April 1, naming it after his new wife. He plans to build a financial empire headquartered at Medora. On June 26 a gunfight occurs west of Little Missouri between a group of men led by the Marquis de Mores, and a party of hunters. Hunter William Riley Luffsey is killed and the Marquis is later charged with his murder. Theodore Roosevelt, a 24 year old New York politician, arrives at Little Missouri on a buffalo hunting trip on September 8. Within days he invests in a local cattle ranch and becomes a semi-permanent resident.

First issue of The Bad Lands Cow Boy, edited by Arthur T. Packard, is published on February 7. Cornerstone of St. Mary's Catholic Church, still in use, is laid on September 20. The Medora-Deadwood stagecoach line, owned by the Marquis de Mores, begins operation on October 6. It will fold seven months later.

Metropolitan Hotel, later renamed the Rough Riders, opens at Medora in February. The Marquis de Mores is acquitted on September 19 of the murder of Riley Luffsey in 1883.

Billings County is organized on April 12, with Medora as county seat.

A terrible winter causes immense loss of stock and transforms the cattle industry. Marquis de Mores and family leave the area following the failure of his businesses.

The Bad Lands Cow Boy ceases operation after the office and press, west of the river, are destroyed by fire on January 12.

North Dakota is granted statehood on November 2.

President Theodore Roosevelt stops at Medora on April 7, his only visit as president. Medora de Vallombrosa, widow of the Marquis de Mores, returns to her home, the Chateau de Mores, for a six week visit in the fall.

De Mores packing plant, unused since 1886, is destroyed by fire on March 17.

Tom Mix, soon to become a famous western movie star, marries Miss Olive Stokes at Medora on January 10.

Three large coal mines operate in Medora area.

Statue of Marquis de Mores is dedicated in De Mores Park.

Chateau de Mores and surrounding property is deeded to the state of North Dakota by a son of the Marquis and Marquise de Mores. Civilian Conservation Corps (CCC) and Works Project Administration (WPA) begin restoration of the house and development of the grounds.

Chateau de Mores State Historic Site opens to the public on August 7.

Theodore Roosevelt National Memorial Park is established on April 25.

South Unit of the National Memorial Park is dedicated on June 4.

Burning Hills amphitheater is constructed west of Medora to host annual drama Old Four Eyes, in honor of Theodore Roosevelt's 100th birthday.

Entrepreneur Harold Schafer and his Gold Seal Company begin modernization and development of Medora as a leading tourist destination.

Rough Riders Hotel is reconstructed by Gold Seal Company, which also purchases the Burning Hills Amphitheater and begins production of the still-running Medora Musical.

Theodore Roosevelt National Memorial Park is designated a National Park on November 10.

New Billings County Courthouse is constructed at Medora.

New de Mores School is constructed at Medora.

Burning Hills Amphitheatre is modernized and expanded.

Billings County Veterans Memorial is dedicated at Medora.

Harold Schafer Center opens at Medora.

Billings County Library/Resource Center is constructed at Medora.

North Dakota Cowboy Hall of Fame opens at Medora.

Medora is designated a Preserve America Community.

Rough Riders Hotel expansion is completed.