Education
He was educated by tutors in the United States and abroad.
He was educated by tutors in the United States and abroad.
Born in Oyster Bay, New York, he was a ninth-generation descendent of Captain John Underhill. Underhill married Henrietta Graham Meyer in 1883. Their three daughters, Margaret Varnum Underhill (born 1885, Katherine Underhill (born 1892), and Dorothy Underhill (born 1894), were raised at the family"s Oyster Bay estate.
A horseman, he was a judge at Madison Square Garden in 1890.
He served as an Army officer in Cuba during the Spanish–American War alongside Theodore Roosevelt. He briefly served as secretary to East. H. Harriman of the Union Pacific Railroad.
In 1884, Underhill bought the Ontare Ranch in the Santa Ynez Valley from Dixie Thompson for $18,000, moving there with his family. Two years later, he purchased 5,260 acres south of Los Alamos, California from Doctor James Barron Shaw in spring 1886.
He wrote Driving for Pleasure: Or, The Harness Stable and Its Appointments in 1896.
In 1900, Underhill divorced Henrietta and moved permanently to California, tired of splitting his time between two coasts.
He was a member of Caroline Astor"s Four Hundred social registry, the Knickerbocker Union, Society of Colonial Wars, Sons of the American Revolution, and the Union Club of New New York