Situated about 160 miles (260 km) north of the Oregon Trail, the region experienced rapid growth in the late 19th century.

was converted by French-Canadian fur traders to the more familiar French word pelouse, meaning "land with short and thick grass" or "lawn."

This larger definition is used by organizations such as the World Wide Fund for Nature, who define the Palouse Grasslands ecoregion broadly.

These four centers, along with at least ten lesser ones, resulted in a diffuse pattern of rural centers, relative to the centralized Walla Walla Country[5] Cities along the borders of the Palouse, and by some definitions included within it, include Lewiston, Idaho, serving the Camas Prairie farmlands; Ritzville, serving the eastern edge of the Big Bend Country; and Spokane, the region's major urban hub.

So dominant was Spokane's position that it became known as the capital of the Inland Empire, including all the wheat-producing regions, the local mining districts, and lumber-producing forests.

By 1910, although local terms like Palouse, Walla Walla Country, Big Bend, Umatilla Country, and Camas Prairie continued to be common, many people of the region began to regard themselves as living in the Inland Empire, the Wheat Belt, the Columbia Basin, or simply Eastern Washington, Oregon, or North Idaho.

The degree of development of individual layers of calcrete together with thermoluminescence and optically stimulated luminescence dating of the loess indicate that each calcrete layer represents a period of thousands to tens of thousands of years of nondeposition, weathering, and soil development that occurred between episodic periods of loess deposition.

A consistent sequence of normal-reverse-normal polarity signatures demonstrates that the older layers of loess accumulated between 2 and 1 million years ago.

Internally, they lack any evidence of cross-bedding or erosion of interbedded layers of loess and calcrete that characterize dunes formed by moving currents.

In addition, the ubiquitous homogenization of the loess by innumerable plant roots and insect burrows as it accumulated further supports the conclusion drawn from numerous thermoluminescence and optically stimulated luminescence dates that individual layers of loess accumulated over an extended period of time in terms of thousands of years.

Lately, conversion of agricultural lands to suburban homesites on large plots invites a new suite of biodiversity onto the Palouse Prairie.

As early as the 1930s soil scientists were noting significant downcutting of regional rivers (Victor 1935) and expansion of channel width.

Higher, faster runoff caused streams to downcut quickly, effectively lowering the water table in immediately adjacent meadows.

The impacts of domestic grazers on the grasslands of the Palouse and Camas Prairies was transitory because much of the areas were rapidly converted to agriculture.

However, the canyonlands of the Snake and Clearwater rivers and their tributaries with their much shallower soils, steep topography, and hotter, drier climate, were largely unsuitable for crop production and were consequently used for a much longer period by grazing domestic animals (Tisdale 1986).

The highly competitive plants of both of these genera evolved under similar climatic regimes in Eurasia and were introduced to the U.S. in the late 19th century.

With the adoption of no-till farming practices in the Palouse region in the early 2000s,[17] the negative environmental impact of agriculture has visibly decreased.

Some animals in the region include both mule and white-tailed deer, coyotes, bobcats, California quails, yellow-bellied marmots, and red-tailed hawks.