Born in New York City, the second child and first son of William Kissam Vanderbilt and Alva Erskine Smith, he was known by the nickname "Willie K" and until his father died was labeled as Vanderbilt Jr. instead of the more formal Vanderbilt II. He was a brother to Harold Stirling Vanderbilt and Consuelo Vanderbilt. Born to a life of luxury, he was raised in Vanderbilt mansions, traveled to Europe frequently, and sailed the globe on yachts owned by his father.
Willie K Vanderbilt was educated by tutors and at private schools and sent to study at Harvard University but dropped out after the first year. Although he developed an interest in horse racing and yachting, he was totally fascinated with automobiles. At age 10, during a stay in the south of France he had ridden in a steam-powered tricycle from Beaulieu-sur-Mer the 7 kilometers to Monte Carlo and as a twenty-year-old, in 1898 he ordered a French De Dion-Bouton motor tricycle and had it shipped to New York. Soon, he acquired other motorized vehicles and before long began to infuriate citizens and officials alike as he sped furiously through the towns and villages of Long Island, New York en route to Idle Hour, his parent's summer estate at Oakdale. In 1899, Vanderbilt married Virginia Graham Fair (1875-1935), a wealthy heiress whose father, James Graham Fair had made a fortune in mining the famous Comstock Lode. They spent their honeymoon at the Idle Hour estate but disaster struck when fire broke out and the mansion burned to the ground.
A skilled sailor, he participated in yacht racing, winning the Sir Thomas Lipton Cup in 1900 with his new 70-foot yacht he had named Virginia in honor of his new bride. In 1902, Vanderbilt began construction on his own country place at Great Neck on Long Island that he named "Deepdale." However, sailing would take second place to his enthusiasm for fast cars. In 1904, Willie K Vanderbilt set a new Land Speed Record of 92.30mph in a Mercedes at the Daytona Beach Road Course at Ormond Beach, Florida. That same year, he launched the Vanderbilt Cup, the first major trophy in American auto racing. An international event, designed to spur American manufacturers into racing, the race's large cash prize drew the top drivers and their vehicles from across the Atlantic Ocean who had competed in Europe 's Gordon Bennett Cup. Held at a course set out in Nassau County on Long Island, New York, the race drew large crowds hoping to see an American car defeat the mighty European vehicles. However, a French Panhard vehicle won the race and fans would have to wait until 1908 when 23-year-old George Robertson of Garden City, New York became the first American to win the Vanderbilt Cup.
While a great part of his life was filled with travel and leisure activities, Willie K Vanderbilt's father put him to work at the family's New York Central Railroad offices at Grand Central Station in Manhattan. As such, in 1905 he joined other Vanderbilts on Fifth Avenue, building a townhouse at number 666. The Vanderbilt Cup auto races repeatedly had crowd control problems and at the 1906 race a spectator was killed. Seeing the potential to solve the safety issue as well as improve attendance to his race, Willie K Vanderbilt formed a corporation to build the Long Island Motor Parkway, one of the country's first modern paved parkways that could not only be used for the race but would open up Long Island for easy access and economic development. Construction began in 1907 of the multi-million dollar toll highway that was to run from the Kissena Corridor in Queens County over numerous bridges and overpasses to Lake Ronkonkoma, a distance of 48 miles. However, the tollroad was never able to generate sustainable profits and in 1938 it was formally ceded to the county governments in lieu of the $80,000 due in back taxes.
His new high-speed road complimented a train service that allowed a rapid exit from Manhattan. Becoming the first suburban automobile commuter, in 1910 Willie K Vanderbilt began work on the much more elaborate and costly "Eagles Nest" estate at Centerport, Long Island. An avid collector of natural history and marine specimens as well as other anthropological objects, he traveled extensively aboard his yacht as well as overland to numerous destinations around the globe. He acquired a vast array of artifacts for his collection during his well-documented travels and after service with the United States Navy during World War I, he published a book titled "A Trip Through Sicily, Tunisia, Algeria, and Southern France." A few years later, he engaged a curator from the American Museum of Natural History to participate with him in a scientific voyage to the Galapagos Islands.
Already extremely wealthy from a Trust fund and from his income as president of the New York Central Railroad Company, on his father's passing in 1920, Willie K Vanderbilt inherited a multi-million dollar fortune. In 1925 he traded a luxury yacht for ownership of Fisher Island, Florida, a place he used as a winter residence. He built a mansion complete with docking facilities for his yacht, a seaplane hangar, tennis courts, swimming pool, and an eleven-hole golf course. In addition to this property, and his Long Island estate, Vanderbilt also owned a farm in Tennessee and Kedgwick Lodge, a hunting lodge designed for his father by architect Stanford White, on the Restigouche River in New Brunswick, Canada.
Vanderbilt and his wife Virginia had a son, William Kissam Vanderbilt III and daughters Muriel and Consuelo, the latter named for her aunt. However, the Vanderbilts separated after ten years of marriage but did not formally divorce until 1927 when he wanted to remarry. Divorce proceedings were handled by his New York lawyers while he and Rosamund Lancaster Warburton (1897-1947), a former wife of an heir to the John Wanamaker department store fortune, waited discreetly away from the media at a home in the Parisian suburb of Passy, France. When the divorce matters were complete, the couple were married at the Hotel de Ville (city hall) in Paris.
In 1933, tragedy struck the Vanderbilt family when his 26-year-old son, William Kissam III, was killed in an automobile accident in South Carolina while driving home to New York City from his father's Florida estate. His son had inherited his fathers love of fast cars and exotic travel and in his memory, Willie K Vanderbilt added a new wing to his Eagle's Nest home in Long Island to house memorabilia, trophies, and souvenirs including those from his son's African safaris. He then opened the estate for public viewing several days a week and organized his will so that that upon his death the Eagle's Nest property along with a $2 million upkeep fund would be given to Suffolk County, New York to serve as a public museum, the Vanderbilt Museum.
Willie Kissam Vanderbilt II died in early 1944 of a heart ailment and was interred in the family mausoleum at the Moravian Cemetery on Staten Island, New York.