Carl Einar Hille (28 June 1894 – 12 February 1980) was an American mathematics professor and scholar.

He received a Ph.D. from Stockholm in 1918 for a doctoral dissertation entitled Some Problems Concerning Spherical Harmonics.

[2] In 1919 Hille was awarded the Mittag-Leffler Prize and was given the right to teach at the University of Stockholm.

In 1933, he became an endowed professor of mathematics in the Graduate School of Yale University, retiring in 1962.

Hille was a member of the London Mathematical Society and the Circolo Matematico di Palermo.