Justus F. Krumbein was a prominent architect in Portland and the Willamette Valley from 1871 until his death in 1907. His work included designs for many significant commercial and residential buildings and the second state capitol in Salem.

Born near Hamburg, Germany, in 1847, Krumbein received formal architectural training at the Polytechnic School of Hanover, graduating in 1867. In 1869, he immigrated to San Francisco, where he remained for two years before relocating to Portland in the fall of 1871. Krumbein joined in partnership with W.G. Gilbert. Little is known of their early projects, but in 1873, Krumbein and Gilbert won a competition to design a new state capitol for Oregon. The plans called for a domed structure, modeled somewhat after the U.S. Capitol in Washington, D.C., but the dome portion of the building was not completed until 1894. The building stood until 1935, when it was destroyed by fire.

Not long after winning the capitol competition, the partnership between Krumbein and Gilbert dissolved, and Krumbein began working with notable Portland architect Warren H. Williams. This partnership lasted only until 1878, but by that time both Krumbein and Williams had become the preeminent designers of Portland’s cast-iron-fronted commercial buildings

In 1878, Krumbein struck out on his own, entering the most extravagant phase of his career. Krumbein’s work during this period included the Bickel Block (1883), which was renovated in 2008 and is now part of the University of Oregon’s Portland campus. In 1884, he designed his most notable cast-iron building, the Kamm Block. The four-story building was a marvel of architectural ornamentation, with hand-carved wooden detailing complementing cast-iron columns and a blend of Renaissance and Gothic styles. The opulence of the Kamm Block and other buildings like it fell out of favor toward the end of the nineteenth century, and in 1949 it was torn down and replaced by a parking lot.

In about 1890, Portland’s cast-iron era ended, and Krumbein’s career began to slow. He designed a few more notable buildings, moving away from the Victorian opulence that defined his earlier career. In 1890, he designed the Perkins Hotel, noted for the life-size wooden steer, painted gold and standing high above the street in an alcove of the building's corner tower. In 1892, he designed the Romanesque-styled buildings Ancient Order of United Workmen Temple in downtown Portland (demolishsed in 2017). Soon after, he won a competition to design the St. Vincent Hospital in northwest Portland. In 1897, he designed the Flavel Hotel. At the time, Flavel was a fledgling resort town near Astoria, later annexed by the town of Hammond. Krumbein also designed a building for the 1905 Lewis and Clark Exposition. The Lewis and Clark Memorial Hall was intended to be one of the fair's few permanent structures, among other things. serving as a home for the Oregon Historical Society. It was never built and was one of the last designs of Krumbein's the distinguished career.

Only a few of Krumbein’s buildings are still standing, but he was one of Portland’s most significant architects of the nineteenth century.