Some studies date the origins of US intercollegiate football—and, by extension, the modern game of American football—back to a soccer-style game played between Princeton and Rutgers universities in 1869. This article joins with others to argue that such a narrative is misleading and goes further to clarify the significance of two “international” fixtures in 1873 and 1874, which had a formative and lasting impact on football in the United States. These games, contested between alumni from England’s Eton College and students at Yale University, and between students at Canada’s McGill University and Harvard University, combined to revolutionize the American football code. Between 1875 and 1880, previous soccer-style versions of US intercollegiate football were replaced with an imported, if somewhat modified, version of rugby football. It was the “American rugby” that arose as a result of these transnational exchanges that is the true ancestor of the gridiron game of today.