It was here that federal indian commissioners negotiated and signed a treaty with many California tribes in the area on April 29, 1851.

The refusal of the Ahwahneechee and Chowchilla tribes to sign the treaty and relocate to the reservation led to the Mariposa War.

[3] To supervise the newly established reservation and protect the booming mining activity on the San Joaquin River, it became clear that a permanent fort was needed.

The fort consisted of a blockhouse, barracks, officers quarters, mess hall and other buildings.

[3] Hostilities with the local tribes had receded by 1858 and the fort was evacuated of military personnel but left with all the buildings intact.

[7] Upon the outbreak of the American Civil War, an informant reported that nearby townspeople had "celebrated the occasion by a public demonstration, in which all joined (of both sexes), by firing a Confederate salute...cheering for them and groaning for the United States government and its officers."

Soldiers were sent back to Fort Miller in 1863 to investigate the situation, but found no such trouble with confederate sympathizers.