Osterman and Siebert was an architectural firm in Walla Walla, Washington. Henry Osterman was senior partner. Osterman was born in Essen, Germany in 1862 The firm's work included Dixie High School and Liberty Theater. Henry Osterman is credited with designing the Electric Light Works Building, Green Park School and Walla Walla Public Library. Outside of Walla Walla the firm designed Preston Hall. Work credited to Henry Osterman and his firm Dixie School (1921) Walla Walla Armory (1920) Courty Courthouse (1916) Preston Hall (1913) in Waitsburg Ellis Hotel Siel Building Walla Walla High School & Gym Central Fire Station Jefferson School City Hall YMCA Building Green Park School Sharpstein School Prospect Point School Masonic Temple Carnegie Library (1905) Central Christian Church Phi Delta Theta House (Whitman College) See also National Register of Historic Places listings in Walla Walla County, Washington Osterman House References 1862 births Year of death missing German emigrants to the United States Architects from Washington (state)