The Nevada State Legislature carved Elko County out of the northeastern part of Lander County on March 5, 1869. Named after its principal town and seat of government, the name Elko occurs elsewhere in the nation associated with railroad stations. The origin of the name is uncertain.

Elko County officials initially occupied three adobe buildings and a tent. Within months, the commissioners accepted the plans of Walter Moberly for a courthouse. "The building is to be...of the Roman Doric style of architecture," reported The Elko Independent. "On the first or lower floor there will be four rooms for offices..., with a fireproof vault in one; and also on this floor five cells for holding prisoners...On the second floor will be the courtroom...and four offices..and a portico in front."

In August 1869, the county commissioners awarded a construction contract for $17,744 to W.P. Monroe. As Monroe began building the courthouse, some people called for a more elaborate design. In spite of the addition of higher walls, a heavy cornice, and alterations to the front stairway, Monroe finished the brick courthouse in a little more than three months, on December 18, 1869.