Joseph Addison Sewall (April 20, 1830 – January 17, 1917) was an American physician, scientist and academic administrator who served as the first president of the University of Colorado from 1877 to 1887.

In preparation, he returned to the east coast where he studied agricultural chemistry at Yale University.

There he was taught chemistry by Eben Horsford, botany by Asa Gray and natural history by Louis Agassiz until 1860.

Offered a teaching position at Illinois State Normal University, Sewall closed his pharmacy and went to Connecticut for additional training.

In addition, he taught natural philosophy, biology, botany, physics, pedagogy, political economy, astronomy, physiology and logic.

[1][3] Sewall also served as director of the U.S. Grass and Forage Experiment Station in Garden City, Kansas.