Construction of a U.S. highway system for automobile traffic began soon after World War I substantially as extensive anti-depression public works. Construction grew also from public support for roads for autos, prior development of plans and funds, and a brief depression's lower building costs. A new highway program expanded quickly in 1920--22, using federal funds states and counties matched, making participation a state or local option. The expansion's extent and location depended partly on existing roadbuilding and taxing systems; on patterns of geography, settlement, and economics; and on wishes of many governments' officials and constituents. In early 1919, Congress had added to 1916 appropriations for the program and designated it to reduce unemployment expected in demobilization. When the economy did slow in 1920--22, better roads were widely in demand, even where government activity to offset depression was unusual. Citizens debated using the program locally to add jobs and spending while markets of farm and factory goods were slow---a proposition opposed by some taxpayers, supported by many in labor unions or commerce, and discussed by voters before referendums on road bonds. Many areas relied less on farmers' labor or taxes, turning to state taxation of vehicles and gasoline for roadbuilding's growing costs. Congress set a hiring preference for veterans: some local groups urged excluding from road work Hispanic or transient white men. Every state spent some of the program's funds, though variations were large. The Midwest outspent the South, North Atlantic, Plains, or West. States paved main routes; elsewhere, they spread improvements among rural areas by low-cost projects of grading or graveling. By mid-1922, an era when few Americans lived near a paved or graveled highway changed, and roads in many areas used new engineering standards, agreed on by state and federal agencies. The federal-aid program lacked the size to change quickly the nation's economic course, though its spending in a depression supported efforts by states and localities in their other roadbuilding. A Progressive effort at balancing economic trends, it provided unemployment relief and economic stimulation in ways later useful in the 1930s and in planning the Interstate system.