This must be the work of Douglas Cardinal, the same one that designed the Canadian Museum of Civilization [now the Canadian Museum of History].
Correct, along with many collaborators, and the two buildings have similar curvilinear elevations. The architectural process
is described in detail on the museum's website:
Some basic parameters for the building structure were dictated by the 4.25-acre trapezoidal site, the building restrictions for the National Mall, and an active creek bed flowing below the site. These challenges were addressed initially by the design team of GBQC and Douglas Cardinal, Ltd., which included consultants Douglas Cardinal (Blackfoot), Johnpaul Jones (Cherokee/Choctaw), Donna House (Diné/Oneida), and Ramona Sakiestewa (Hopi).
The building’s distinctive curvilinear form, evoking a wind-sculpted rock formation, grew out of this early work, forming the basis for the architecture. Following this conceptual design work, the project was further developed by Jones, House, and Sakiestewa, along with the architecture firms Jones & Jones, SmithGroup in collaboration with Lou Weller (Caddo) and the Native American Design Collaborative, and Polshek Partnership Architects. This extended collaboration resulted in a building and site rich with imagery, connections to the earth, and layers of meaning. The building is aligned perfectly to the cardinal directions and the center point of the Capitol dome, and filled with details, colors, and textures that reflect the Native universe.
This is arguably the most difficult public building in Washington's "monumental core" to photograph. It's impossible to get a good angle on the entire structure from street level and the rooftops of the few nearby buildings which offer an unobstructed view are off-limits to the general public. You need to walk around it to get a sense of the entire structure, which is well-depicted in this graphic from the museum's website:
I used to work directly across the street from the museum, and watched it being constructed. I've shot it from various angles, but the image I posted earlier in this thread, made in 2014, is my favorite.
