Future tycoon Henry Morrison Flagler's calling as a businessman came early. Born in Hopewell, New York, on January 2, 1830, Flagler left school at 14 to seek his fortune in Bellevue, Ohio. Before long, young Henry advanced from L.G. Harkness and Company's grain store to its sales staff, increasing his salary from five dollars a month to $400.

In 1852 Flagler and his half-brother, Dan Harkness, established D.M. Harkness and Company. Here, Flagler made an acquaintance that would alter his, and Florida's, destiny. John D. Rockefeller was a D.M. Harkness employee when he gave up grain for oil. By the mid-1860s, Cleveland, Ohio, had become the center of America's oil-refining industry. When Flagler gave Rockefeller capital to back his new oil refinery, an oil giant was born. Standard Oil, headed by partners Rockefeller and Flagler, commenced operations in January 1870 and within two years stood at the forefront of the U.S. oil industry.

In 1877 Flagler, his wife, Mary Harkness, and their two children relocated to New York City. Mary's health had been deteriorating for years, and on doctor's orders, the Flaglers tried wintering in Jacksonville, Florida, then the only accessible city in the state. Despite the excellent weather the Flaglers enjoyed in Florida, Mary remained in poor health and died in 1881 at age 47.

Flagler's second trip to Florida, with second wife Ida Alice Shourds, convinced him to pour his oil fortune into the state's development. Shortly after their marriage in 1883, the newlyweds visited St. Augustine. Flagler was again charmed by the weather but frustrated by the inadequate hotel and transportation facilities.

Flagler embarked upon a career change: railroad and hotel magnate. In 1885 he began work on the Ponce de Leon Hotel in St. Augustine. But inaccessible accommodations weren't a wise investment, so Flagler bought two Northern Florida railroads and formed a new railway company which would become the Florida East Coast Railway. He extended his Railway to St. Augustine and then lengthened the track, first to current-day Daytona Beach, then to Fort Pierce, and finally to Palm Beach. Flagler followed the success of the Ponce de Leon, which opened in 1888, with the 1,150-room Royal Poinciana Hotel in Palm Beach, establishing Palm Beach as a vacation spot for wealthy Northerners.

A combination of inclement weather and personal strife carried Henry Flagler further south still. The real estate boom triggered by Flagler's railroad weakened in the winter of 1894-1895, when two unexpected freezes destroyed northern Florida's citrus crop. Legend has it that Miami landowner Julia Tuttle, a young widow who lived in Miami and advocated development, sent Flagler a spray of orange blossoms--proof that the freeze had left southern Florida untouched--as incentive to extend his railroad to Miami.

Flagler seized the opportunity, and the boom was on again, now in Miami. Flagler's home life, however, was deteriorating. His wife, Ida, whose behavior had become frighteningly erratic since the beginning of their marriage, was diagnosed with "delusionary insanity," and her subsequent institutionalization left Flagler "almost prostrated with grief and anxiety."

The prescribed remedy for Flagler's despondence was, fittingly, a vacation in Florida. He fell in love with the place and stayed to begin a new career in Florida. Later, he negotiated land deals with Julia Tuttle and Miami's other prominent landholders, the Brickells, and in 1896, his Florida East Coast Railway reached Miami. That same year, Miami was incorporated, and residents rallied to rename the city Flagler. Its benefactor declined the honor. (Florida's 53rd county was eventually named for him.)

But Miami was not enough for the man who described himself as "contented, but…never satisfied." Flagler now planned a railroad that would reach from Miami to Key West, spanning seven miles of open water. The Florida Overseas Railroad, begun in 1905 and derisively called "Flagler's Folly," would be his least successful endeavor. Hurricanes and torrential downpours stalled construction several times, and hundreds of men died in a 1906 storm. Completed in 1912, the bridge was, as predicted, a commercial failure, and in 1935 fell to a brutal Labor Day hurricane.

Henry Flagler died at age 83, on May 20, 1913, as a result of injuries he sustained in a fall at Palm Beach's Whitehall, the 55-room mansion he built as a wedding gift for his third wife. As a funeral train carried his body to St. Augustine, "'every wheel of the Florida East Coast Railway remained motionless for a period of ten minutes in silent tribute to its great builder.'"