Henry began designing buildings as early as the 1880s and in 1903 settled in El Paso, where he and his brother Gustavus co-founded Trost & Trost. A third brother, Adolphus, joined the firm in 1908 and introduced the technology of reinforced concrete construction to the region, making possible the modern high-rise.
The firm designed many of the most beautiful buildings in El Paso, including the Caples Building (1909), Anson Mills Building (1911), Hotel Paso del Norte (1912), El Paso High School (1916), Popular Dry Goods Co. (1917), Hotel Cortez (1926), Bassett Tower (1930), and Hilton Hotel (1930).
Henry and his brothers were capable of designing a wide variety of building types and in every conceivable style, including Classical, Romanesque, Renaissance Revival, Pueblo, Art Deco, Moorish, and even Bhutanese. 27 of the 39 buildings the firm designed in downtown El Paso are still standing, and there are hundreds more situated throughout El Paso and the Southwest.
The Trost Society mapping project stems from research that was conducted by the late Dr. Lloyd C. Engelbrecht and his late wife June-Marie Engelbrecht, who had won a National Endowment for the Humanities grant to study the Trost legacy nearly 30 years ago.