Franklin Burnet Sprague (July 16, 1825 – February 7, 1895) was an American military officer, businessman, and judge.

While building a road near Fort Klamath, Sprague led a party into the Cascade Mountains to investigate Crater Lake.

Like the majority of Oregonians at the time, Sprague was a strong supporter of the Union during the American Civil War.

[1][2] In 1864, Sprague joined the Union Army, and was commissioned as a Captain in the 1st Oregon Volunteer Infantry Regiment.

He participated in a number of skirmishes with the Northern Paiute and other Indian bands in southeastern Oregon.

After the construction work was completed, Sprague published a list of the best camp sites along the road in the Jacksonville newspapers so that the wagon masters could find the best water and grass along the way.

[7] On August 1, 1865, two hunters from Sprague's road construction crew rediscovered Crater Lake, which had been first visited in 1853, but was never effectively recorded so that others could locate it.

[2][7] Sprague's account of the visit was reported to Jacksonville's leading newspaper, the Oregon Sentinel on August 25.

[7][8] ...you sit down on the brink of the precipice, and feast your eyes on the awful grandeur, your thoughts wander back thousands of years to the time when, where now is a placid sheet of water, there was a lake of fire, throwing its cinders and ashes to vast distances in every direction.

The appearance of the water in the basin, as seen from the top of the mountain, is that of a vast circular sheet of canvass, upon which some painter had been exercising his art.

In 1875, Sprague ran as the Democratic Party's candidate for Delaware County Probate Judge, and was elected.

[1][2] Sprague played an important part in the early history of Crater Lake National Park.