John Jacob Astor IV was born at Ferncliff Farm in Rhinebeck, New York, the youngest of five children to William Backhouse Astor Jr. and Caroline Webster 'Lina' Schermerhorn Astor. His birth marked his place within the prominent and wealthy Astor family.

Astor spent his childhood immersed in the high society of New York, experiencing a life of immense privilege and access to the best resources. He was exposed to the world of business and real estate from a young age, influenced by his father's and grandfather's legacy.

Astor received his education at St. Paul's School in Concord, New Hampshire, followed by Harvard University. While his academic performance wasn't stellar, his education broadened his worldview and provided him with valuable connections and social skills crucial for navigating the elite circles of New York society.