In the military history of the Presidio, and even the whole US Army, few people loom as large as General John Pershing. He was the senior Army officer, known as General of the Armies, serving 1886–1924. He was especially distinguished in World War I and for his mentorship of many generals following him.
Super-much less racist than the President (Woodrow Wilson) he served under, he found a way to allow all-Black units to fight combat roles in WWI despite a prohibition on their regular (or equal) participation with white units.
The whole of Pershing Square is named for him, and the flagpole marks his former home on the Presidio.