In the early 1920s, Frank Lloyd Wright built a series of four experimental "textile block" houses in Los Angeles. After designing his first California commission – the Hollyhock House for Aline Barnsdall – in 1921, and while finishing the second Imperial Hotel in Japan (1915-1923), Wright shifted his focus towards developing a method for affordable residential building. Wright became interested in the potential of concrete block as a means to simplify the process of construction. He resolved to elevate the ubiquitous material into a "noble" one through the application of unifying geometric motifs as wells as through the concealment of joints and reinforcing. Of the four textile block houses constructed, the Ennis House was the last to be designed and built, and at 6,000 square feet, it is also the largest and most monumental of the series.