Woodrow Wilson began as a scholar of government, teaching at Bryn Mawr and Wesleyan before joining Princeton in 1890. As Princeton's president from 1902 he promoted educational reform but encountered opposition over institutional priorities. Elected governor of New Jersey in 1910, he supported progressive measures and gained a national political following. He won the presidency in 1912 amid a split between Republicans supporting William Howard Taft and Theodore Roosevelt.

Wilson's New Freedom program brought tariff reductions, the Federal Reserve Act, and antitrust measures including the Federal Trade Commission. Later reforms addressed labor and agricultural credit. These achievements coexisted with the expansion of segregation in federal workplaces and his tolerance of policies that disadvantaged Black employees. His administration intervened in Latin America, including occupation of Haiti, and pursued a troubled policy toward revolutionary Mexico. His language of self-government did not apply equally to all peoples affected by American power.

Wilson sought neutrality after the First World War began and won reelection in 1916. Unrestricted submarine warfare and other developments led him to ask Congress for war against Germany in April 1917. Mobilization expanded federal economic authority and the armed forces, while the Espionage and Sedition Acts facilitated repression of dissent. In January 1918 he announced the Fourteen Points as principles for peace. At the Paris Peace Conference in 1919 he secured a League of Nations covenant but compromised on many other aims, including territorial and colonial settlements.

The Senate rejected the Treaty of Versailles amid disagreement over the League and congressional authority. Wilson's refusal to accept reservations contributed to the failure. During his campaign for public support he suffered a major stroke in October 1919; the severity of his incapacity was concealed while his wife Edith and advisers controlled access. He received the Nobel Peace Prize for 1919 and left office in 1921. He died in 1924. His career helped transform domestic financial institutions and the international role of the presidency, but racial exclusion, intervention, wartime repression, and inflexibility are integral to its assessment. His internationalism influenced later plans for collective security even though the United States did not enter the organization he had helped create.