He served the military as a tracker and guide, including during the Mormon Utah War, following the Meeker Massacre, and during the Battle of the Rosebud in present day Big Horn County, Montana.

In 1873, Baker built a cabin with a guard tower near the Little Snake River in Wyoming, where he raised livestock until his death in 1898.

James Baker was born on December 19, 1818, in Belleville, St. Clair County, Illinois,[1] a few miles from St. Louis, Missouri.

[2] Baker was hired by Jim Bridger to work for the American Fur Company for 18 months, for which he received $465 (equivalent to $13,305 in 2023).

On May 15, 1838,[a] he left St. Louis by boat[1] and traveled up the Mississippi and Missouri Rivers[6] to the Uinta Mountains of present day Utah and Wyoming.

[1] Baker led a pack train to the Rocky Mountain Rendezvous in the Wind River Valley for Jim Bridger.

Baker traveled from the Green River, to Bridger's camp at the Henry's Fork, arriving in early August.

Bridger, who was worried about his overdue associate Henry Fraeb, sent Baker and others to search for the lost party[1] and to warn them of increased hostility among the Plains Indians.

Fraeb was found at the base of Squaw Mountain on the banks of the Little Snake River and Battle Creek, near what is now the border between Wyoming and Colorado.

[3] The trappers hid behind stumps, dug pits, and created a defensive barrier of dead horses and logs.

[1] Baker continued to hunt and trap in the Henry's Fork area independent of a fur company.

He was a generous, noble-hearted specimen of the trapper type, who would peril his life for a friend at any time, or divide with him his last morsel of food.

His brother married a Shoshone woman and established a cattle ranch near Henry's Fork in Wyoming.

[11] Jim Baker was known for his skills as a marksman, archer, horseman, tracker, hunter, and lariat thrower.

[14] Baker camped with the Shoshone in the Wind River area,[11] assuming the clothing and lifestyle of the Native Americans.

[1][15][c] Baker continued to live with his wife's tribe, as was common when mountain men married Native American woman.

[16] Baker operated at least one trading post and ferry stop on the Oregon - California - Mormon Trails along the Green River south to Salt Lake City.

In 1847, Baker was in the Salt Lake City, Utah, region, where he worked for a railroad party as a scout and guide.

On their return, the troops passed through present-day Denver area and discovered gold at Cherry Creek in early 1858.

[1] While practicing with his Spencer carbine weapon, the magazine exploded, which injured his face and blew his right thumb off its hand.

In 1873, Baker left Colorado and bought a ranch in the Little Snake River Valley near Savery, Wyoming.

He built a hand-hewn log cabin, that looked like and served as a fort for settlers following the Meeker Massacre (September 29, 1879).

Baker served under General George Armstrong Custer during the Battle of the Rosebud in the Black Hills against Crazy Horse, the Oglala Lakota chief in 1876.

[23] Jim Baker was married three[1] or more times, perhaps with as many as six wives,[19] including women from the Shoshone, Snake, Bannock, and Flathood tribes.

[15] Baker fell in love with Flying Fawn, a Sioux woman and daughter of Long Lance.

[10] They had ten children: Thomas, Buck, Jim, Mary, Isabel, Madeline, Nancy Kate, Liza, and Elsie.

[5] By that time, none of his wives were with him and there were only six children who settled with him: Baker continued to live out his life at his cattle ranch and cabin.

In July 1976, the home of Jim Baker was returned to Savery, Wyoming and is now located at the Little Snake River Museum.

The cabin was reconstructed under the direction of Jim Baker's great-grandson, Paul McAllister of Dixon, Wyoming.