From 1700 to 1750, the tribes of the Sioux Nation clash with the Arikara, Mandan and Omaha for control of eastern Dakota. By the late 1700s, the Sioux Nation dominates the northern Plains.


The Verendrye brothers, the first Europeans to see the Black Hills, bury an inscribed lead plate near present-day Fort Pierre, claiming the land for France. The plate is now displayed at the Cultural Heritage Center in Pierre.


Meriwether Lewis and William Clark explore present-day South Dakota’s stretch of the Missouri River. The explorers and the Yankton and Teton Sioux have their first historic meetings here. Today, state highways 1804 and 1806 commemorate the expedition’s trip up the Missouri River in 1804 to the Pacific Ocean and the return journey in 1806.


The Yellowstone, the first steamboat on the Missouri River, paddles to Fort Tecumseh (at present-day Fort Pierre). Trade flourishes along the river. The first permanent white settlement in South Dakota is established here.


Yankton is named capital of newly organized Dakota Territory. The territory includes present-day South and North Dakota and much of Wyoming and Montana. There’s a replica of the Territorial Capitol in Yankton’s Riverside Park.


The U.S. Army establishes Fort Wadsworth on the Dakota prairie. The fort is built to provide protection to the new settlers in the region. Now known as Fort Sisseton, the army post stands as one of the nation’s best-preserved military forts.


An expedition led by Lt. Col. George A. Custer discovers gold in the Black Hills. By 1876, gold fever spreads throughout the Hills. Deadwood, one of the West’s most famous mining camps, draws characters like Wild Bill Hickok, Calamity Jane and Potato Creek Johnny. They’re buried in historic Deadwood’s Mount Moriah Cemetery.


With a posse hot on his trail, Jesse James spurs his horse across Devil’s Gulch, near present-day Garretson. The gulch is about 20 feet wide and 50 feet deep. Jesse takes the leap, as members of the posse watch in disbelief, and the notorious outlaw rides away.


Pioneering farmers begin the rush for land known as the “Great Dakota Boom.” The next year, the now-famous pioneering family of Charles Ingalls settles in De Smet, the “Little Town on the Prairie.” Later, the town serves as the setting for five of Laura Ingalls Wilder’s books.


South Dakota achieves statehood. Pierre becomes the temporary capital, but several cities vie for the permanent post. The issue isn’t settled for nearly 20 years.


The 7th Cavalry kills more than 250 Lakota men, women and children in what comes to be known as the Wounded Knee Massacre. A solitary stone monument near the town of Wounded Knee marks the site of this tragedy.


Sculptor Gutzon Borglum begins work on Mount Rushmore National Memorial. He intends to carve the four presidents to their waists but dies in 1941 before the work is finished.


The first electric cooperative in South Dakota is organized in 1935 in Burbank. Many other cooperatives followed bringing electricity to rural South Dakota.


The U.S.S. South Dakota is launched. On two separate occasions, the Japanese report sinking the South Dakota, which downed 64 planes during World War II. For security purposes, the ship is renamed “Battleship X.”


The Pick-Sloan flood control act is passed, funding four dams on the Missouri River in South Dakota. Today, the dams control flooding, harness the river’s energy and provide recreational opportunities.


The first blast takes place on the Crazy Horse Memorial mountain carving in the Black Hills. The memorial is a tribute to Native Americans. The family of sculptor Korczak Ziolkowski (1908–1982) continues the nonprofit project today.


About 200 armed members of the American Indian Movement occupy Wounded Knee to protest policies towards Native Americans.


South Dakota celebrates its centennial.


The WWII Memorial on the Capitol grounds in Pierre is unveiled. It is the first of its kind in the nation.


The state celebrates is quasquicentennial – the 125th anniversary of its statehood.

Source: https://www.travelsouthdakota.com/before-you-go/about-south-dakota/south-dakota-timeline