Around the age of fifteen, he attended Sewanee College, but returned his hometown to study at the Carroll Masonic Institute in 1870 and 1871.
After withdrawing to a ranch to recover from tuberculosis, he accepted a position at the University of Texas as an instructor in history and English literature.
He ascended the academic ranks, culminating in an appointment as Professor in 1897, while retaining his position as chair throughout his tenure.
He edited the first seven volumes of the journal, and co-edited it with Herbert E. Bolton and Eugene C. Barker starting in 1904.
Guy Morrison Bryan, a descendent of the Austins, worked with Garrison to convey these documents to the University of Texas.