Irish-born Robert A. O’Hara, retained by Marcus Daly as land agent and developer of Daly’s “company town,” came to the Bitterroot Valley in 1890. O’Hara had the distinction to serve as the first mayor of the town of Hamilton from 1894 to 1896. Having purchased these choice lots, O’Hara built this home in 1896, initially a modest one-story dwelling. The family grew to include three daughters, while O’Hara established himself as a prominent attorney in private practice and as Daly’s water rights attorney. Remodeling of the home circa 1909 attests to O’Hara’s success and community status. Eric Trosdahl, the original builder, added the south parlor and second story with the narrow clapboard siding at that time. A low-pitched Prairie style roof with extended eaves combines with the wider clapboard siding and cornerboards of the first floor to create a handsome blend of stylistic elements. Narrow bays emphasize the vertical lines and exaggerate the height of this gracious residence, which was home to Robert O’Hara until his death in 1954.