[4] He began his architectural career as an apprentice at the studio of Peter Behrens from 1908 to 1912,[5] where he was exposed to the current design theories and to progressive German culture.

[6] Ludwig Mies renamed himself as part of his transformation from a tradesman's son to an architect working with Berlin's cultural elite, adding "van der" and his mother's maiden name "Rohe"[7][8] and using the Dutch "van der", because the German form "von" was a nobiliary particle legally restricted to those of German nobility lineage.

[11] The couple separated in 1918, after having three daughters: Dorothea (1914–2008), an actress and dancer who was known as Georgia, Marianne (1915–2003), and Waltraut (1917–1959),[12] who was a research scholar and curator at the Art Institute of Chicago.

[13] In 1925, Mies began a relationship with designer Lilly Reich that ended when he moved to the United States; from 1940 until his death, artist Lora Marx (1900–1989) was his primary companion.

Mies carried on a romantic relationship with sculptor and art collector Mary Callery for whom he designed an artist's studio in Huntington, Long Island, New York.

Nevertheless they remained on good terms, spending Easter together in 1948 at a modern farmhouse renovated by Mies on Long Island, as well as meeting several more times that year.

Progressive thinkers called for a completely new architectural design process guided by rational problem-solving and an exterior expression of modern materials and structure rather than what they considered the superficial application of classical facades.

While continuing his traditional neoclassical design practice, Mies began to develop visionary projects that, though mostly unbuilt, rocketed him to fame as an architect capable of giving form that was in harmony with the spirit of the emerging modern society.

Like many other avant-garde architects of the day, Mies based his architectural mission and principles on his understanding and interpretation of ideas developed by theorists and critics who pondered the declining relevance of the traditional design styles.

He selectively adopted theoretical ideas such as the aesthetic credos of Russian Constructivism with their ideology of "efficient" sculptural assembly of modern industrial materials.

Mies found appeal in the use of simple rectilinear and planar forms, clean lines, pure use of color, and the extension of space around and beyond interior walls expounded by the Dutch De Stijl group.

[24]: 319  Mies and Gropius both joined the visual arts section of the Reich Culture Chamber and entered early Nazi architectural competitions, with designs showing structures decorated with swastikas.

[24]: 341 He accepted a residential commission in Wyoming and then an offer to head the department of architecture of the newly established Illinois Institute of Technology (IIT) in Chicago.

He focused his efforts on enclosing open and adaptable "universal" spaces with clearly arranged structural frameworks, featuring prefabricated steel shapes filled in with large sheets of glass.

His architecture, with origins in the German Bauhaus and western European International Style, became an accepted mode of building for American cultural and educational institutions, developers, public agencies, and large corporations.

The exterior curtain walls are defined by projecting steel I-beam mullions covered with flat black graphite paint, characteristic of Mies's designs.

The balance of the curtain walls are of bronze-tinted glass panes, framed in shiny aluminum, and separated by steel spandrels, also covered with flat black graphite paint.

Without solid exterior walls, full-height draperies on a perimeter track allow freedom to provide full or partial privacy when and where desired.

This configuration created a feeling of light, openness, and freedom of movement at the ground level that became the prototype for countless new high rises designed both by Mies's office and his followers.

Although now acclaimed and widely influential as an urban design feature, Mies had to convince Bronfman's bankers that a taller tower with significant "unused" open space at ground level would enhance the presence and prestige of the building.

During 1951–1952, Mies designed the steel, glass, and brick McCormick House, located in Elmhurst, Illinois (18 miles west of the Chicago Loop), for real-estate developer Robert Hall McCormick, Jr. A one-story adaptation of the exterior curtain wall of his famous 860–880 Lake Shore Drive towers, it served as a prototype for an unbuilt series of speculative houses to be constructed in Melrose Park, Illinois.

Considered one of the most perfect statements of his architectural approach, the upper pavilion is a precise composition of monumental steel columns and a cantilevered (overhanging) roof plane with a glass enclosure.

The simple square glass pavilion is a powerful expression of his ideas about flexible interior space, defined by transparent walls and supported by an external structural frame.

His own work as architect focused on intensive personal involvement in design efforts to create prototype solutions for building types.

[44] Technological advances in the manufacturing of architectural glass generated renewed interest in Mies's 1922 designs for a high-rise block on Friedrichstrasse in Berlin.

Technological limits meant that Mies's vision for a "skin and bones" architecture, where the steel frame was exposed internally and externally could never be fully realized.

[1] While Mies van der Rohe's work had enormous influence and critical recognition, his approach failed to sustain a creative force as a style after his death.

The archive consists of about nineteen thousand drawings and prints, one thousand of which are by the designer and architect Lilly Reich (1885–1947), Mies van der Rohe's close collaborator from 1927 to 1937; of written documents (primarily, the business correspondence) covering nearly the entire career of the architect; of photographs of buildings, models, and furniture; and of audiotapes, books, and periodicals.

The Ludwig Mies van der Rohe Collection, 1929–1969 (bulk 1948–1960) includes correspondence, articles, and materials related to his association with the Illinois Institute of Technology.

The Ludwig Mies van der Rohe Metropolitan Structures Collection, 1961–1969, includes scrapbooks and photographs documenting Chicago projects.