John Jacob Astor IV was born at Ferncliff Farms in Rhinebeck, New York, to William Backhouse Astor, Jr. and Caroline Webster 'Lina' Schermerhorn Astor. His birth cemented his place within one of America's wealthiest and most influential families, guaranteeing him a life of privilege and shaping his future trajectory in business and society.

Astor displayed an early entrepreneurial spirit, investing in various ventures and even patenting inventions. He invented a bicycle brake and a vibratory disintegrator used to extract gas from peat. These early forays into business demonstrated his inventive mind and foreshadowed his later success in real estate and other industries.