1783 "The treaty of September 3, 1783, ending the Revolutionary war was negotiated years before the present State of Wyoming had a single white inhabitant. But that treaty fixed the western boundary of the United States at the Mississippi River, which twenty years later led to the purchase of the Province of Louisiana, in which the larger part of Wyoming was included." (History of Wyoming, Volume 1, p. 642 by Bartlett)
1873 Captain William A. Jones with his exploration party reached Two Ocean Pass. He wrote; "At this divide occurs a curious phenomenon, probably the one referred to by the early trappers as the 'Two Ocean Pass.' Marching at the head of the column where the trail approached the summit, I noticed that the riband of meadow in which the stream lay we had been following suddenly dropped away in front of us with a contrary slope. I could still see the stream threading it, and for a moment could scarcely believe my eyes. It seemed as if the stream was running up over this divide and down into the Yellowstone behind us. A hasty examination in the face of the driving storm revealed a phenomenon less startling perhaps, but still of remarkable interest. A small stream coming down from the mountains to our left I found separating its waters in the meadow where we stood, sending one portion into the stream ahead of us, and the other into the one behind us—the one following its destiny through the Snake and Columbia Rivers back to its home in the Pacific; the other, through the Yellowstone and Missouri, seeking the foreign water of the Atlantic by one of the longest voyages known to running water. On the Snake River side of the divide the stream becomes comparatively large at once, being fed by many springs, and a great deal of marsh."
1964 The Wilderness Act of 1964 was approved by Congress on September 3, 1964. It was passed in order to preserve and protect certain lands “in their natural condition” and thus “secure for present and future generations the benefits of wilderness.” According to the Wyoming Wilderness Association, "with the passage of the Wilderness Act in 1964, the following Wilderness Areas were established in Wyoming:
- Bridger Wilderness in the Bridger-Teton National Forest—383,300 acres
- North Absaroka Wilderness in the Shoshone National Forest—359,700 acres
- South Absaroka Wilderness (changed to the Washakie Wilderness in 1972 in the Shoshone National Forest—505,552 acres
- Teton Wilderness in the Bridger-Teton National Forest—563,460 acres"