Centuries ago, the area now covered by Lincoln County contained an east–west passageway used by indigenous peoples.

A spring near the present-day Davenport created a large overnight camping place.

The early exploration of the Northwest Territory by Lewis and Clark did not reach as far north as the Lincoln County expanses.

The first recorded entry by European explorers was of David Thompson, a scout for the North West Company, who traversed the area in 1811.

That stretch of the Columbia River is now tame, because of the presence of Grand Coulee Dam.

[6] After this, there was considerable exploration by fur trappers and others, including famed Scottish botanist David Douglas in 1826.

Completion of the Northern Pacific Railway in 1883, and construction of Fort Spokane (1880-1882) hastened settlement.

Lincoln County lies on the Channelled Scablands, known as the Big Bend Plateau.

It lies 1,500-2,500 feet above sea level, with a system of channels eroded into bedrock by glacial rivers and streams, flowing from northeastern Washington.

Due to the relatively level terrain (about 1,200 feet difference from lowest to highest elevations), temperatures tend to vary little from east to west.

Precipitation varies from an arid condition in the western part of the county to semi-arid in the northeast.

The entire area lies in the dry intermontane basin between the Cascades and the Rocky Mountain System.

Monthly temperature averages range from below freezing in mid-winter to highs of 65-71 °F in mid-summer.

[22] Only about 500,000 of 900,000 acres (2,000 of 3,600 km2 (1,390 sq mi)) of farmland in the county are planted in any given year due to the practice of typically harvesting one crop every two years ("summer-fallow"), a necessity in a region with only 12 inches (300 mm) of precipitation annually.