The U.S. has many of the best universities in the world, but according to a new global list, it doesn’t have the best.

The University of Oxford, the oldest in the English-speaking world, took the top spot in the latest World University Rankings, released annually by Times Higher Education. The English university dating to 1096 dethroned the California Institute of Technology, a small, private school in Pasadena that had ranked No. 1 for five-straight years, according to Times Higher Education, a London magazine that tracks...