After the Chicago Columbian Exposition closed in October of 1893, no plans were too big for its director, the architect Daniel Burnham. His scale of operation was now the city: Chicago of course, Cleveland, San Francisco McMillan's Washington, and even distant Manila in the Philippines. By the time of his death in 1912, Burnham's was the largest architecture office in the world.
In that context, even the project for the New York offices of the Fuller Company--the legendary general contractor of the early Chicago skyscrapers--wouldn't have been too important a job. Still, Burnham made the most of it, to the point that even today that area of Manhattan, the Flatiron District, is named after the building.
Burnham took the acute angle where Broadway meets Fifth Avenue and simply run with it. The success (genius?) of the project was to recognize the extraordinary potential of the site--everything, from its geometry to its orientation in the city--and then do almost nothing (yes, the choice of words is not totally innocent.) He starts with a 22-story regular steel frame--the specialty of the Fuller Company--to then wrap it with a sheet of glazed terra-cotta. And not much else, limestone at street level and a muscular crowning, but not even the articulation of the corner or the expression of the verticals. The iconic quality of the Flatiron stems from the unambiguous preeminence of the whole over the parts.
The Flatiron Building stands as an exception to the characteristic skyscrapers of New York, with their tower shafts and iconographic tops. It would take another half a century and another architect coming Chicago for a similar feat: Mies van der Rohe's Seagram Building.