Sir Niall Campbell Ferguson (born April 18, 1964, in Glasgow, Scotland) is a prominent British-American historian, author, and senior fellow specializing in economic and financial history. He grew up in Scotland and earned his BA (1985) and PhD (1989) in History from Magdalen College, Oxford. His academic work focuses on the history of money, empire, international finance, the rise and fall of civilizations, the impact of wars on economies, and the dynamics of global power, blending rigorous scholarship with accessible writing for broader audiences.

Ferguson has held numerous prestigious academic positions, including professorships at the London School of Economics, New York University, and Harvard University. He is currently the Milbank Family Senior Fellow at the Hoover Institution at Stanford University and a senior fellow at Harvard's Belfer Center for Science and International Affairs. He has also been a visiting lecturer at the London School of Economics (2023/2024) and Tsinghua University (2019–2020). In 2021, he co-founded the University of Austin to foster free inquiry in higher education.

His prolific output includes bestselling books such as 'The Pity of War' (1998), 'Empire' (2003), 'Colossus' (2004), and 'Civilization' (2011), which have shaped public discourse on historical and contemporary global issues. He is known for his conservative-leaning commentary, contributions to outlets like The Wall Street Journal, and the PBS documentary series 'The Ascent of Money' (2008), which he also authored as a book. Ferguson has faced criticism for his support of the Iraq War, views on Western imperialism, and public statements on topics like Brexit and financial crises.

He holds dual British and American citizenship, is married to author and activist Ayaan Hirsi Ali (since 2011), and resides primarily in the United States.