The first Irish-American architect to achieve fame in his chosen profession, Louis Henry Sullivan was the son of a Cork-born dancing master who was parted at the age of 13 from his own entertainer father at an Irish market day. The dispossessed youth  made his way to Boston via England and established himself with the upper echelons of society, helped by marriage to a woman of French-Swiss origin.  

    Louis never fully overcame the legacy of his father's difficult and colorful past, and his personal life and circumstances (he never married and had difficulty in family relationships) suggest a pre-occupied, intense and distant figure. Yet he was to enjoy great success in his chosen area, creating a body of work unrivalled in his period, and, in terms of its philosophy, interpretation and impact, before or since.

    Educated briefly at the Massachussetts Institute of Technology and the Ecole des Beaux Arts in Paris, he learned his draughting trade at professional offices in Philadelphia and Chicago, becoming a partner at 27 in the practice of Dankmar Adler and taking over the practice two years later when Adler retired.

    From the beginning Sullivan drew together a number of seemingly incompatible strands of architectural thinking, bringing a dense theory of art and folkloric mysticism to projects that were mainly commercial, adding elaborate ornamentation to interiors that were designed for straightforward administrative function, and introducing height as an aesthetic concept in an era before demand dictated it.

    From 1888 a young Frank Lloyd Wright was Sullivan's acolyte and assistant, receiving a loan from his mentor so that he could build a house and studio for himself, and then designing a house for Sullivan. Wright's moonlighting led to a parting of the ways in circumstances that Wright regretted for the rest of his life, and that led Sullivan to cut off communication for over twenty years. Their reconciliation was prompted by Sullivan's enduring belief that Wright was his natural successor and "the keeper of the sacred flame of architecture."

    Sullivan's most inspired and most successful buildings were in a ten year period from the late 1880s, as he rode on the coat-tails of a great urban rebuilding programme following the Chicago Fire of 1871. His Auditorium Building and Tower (whose 17-storey elevation included the architect's own offices) became one of his most interesting buildings in terms of changing useage, and still functions as a performing arts center and college facility.  He added the Chicago Stock Exchange Building in 1893. At the other end of the timeline, his Prudential Building (1899) is his last notable gift to the skyline of the city he loved.

    Though he never sought a national reputation or portfolio, his practice always had a strong regional outreach to centers such as St. Louis (where his Wainright Building  was completed in 1891) and Buffalo (location of the Guaranty Building completed in 1895). These are considered among his most outstanding buildings.

    During the early 20th. century he turned his attention to smaller cities such as Owatonna, Minnesota (National Farmers Bank, 1908) and Grinnell, Iowa (Merchant's Bank, 1914). At the same time he began to formulate his theories of organic architecture in monographs and books, enhancing his reputation as a deep thinker and a refreshing theorist.  

    With the resignation of his chief draftsman George Grant Elmslie in 1909, the major impetus of the famous practice was halted and the pace of decline accelerated until Sullivan was found dead in a hotel room in Chicago at the age of 68.