The influential author whose works on democracy in the United States profoundly influenced Western political ideologies was Alexis de Tocqueville. His seminal book, "Democracy in America," published in the 1830s, provided an in-depth analysis of American society, political institutions, and the nature of democracy. Tocqueville's observations on equality, individualism, and civic engagement significantly shaped how democracy is understood and practiced. His insights revealed both the strengths and weaknesses of democratic systems, influencing political thinkers and policymakers across Europe and inspiring later discussions on the nature of governance and freedom.