Detlef Lienau (17 February 1818 – 29 August 1887) was a German architect born in Holstein. He is credited with having introduced the French style to American building construction, notably the mansard roof and all its decorative flourishes.
Detlef Lienau, a German architect born in Holstein, is known for his significant contribution to American architecture by popularizing the French style, particularly through the introduction of the mansard roof and its intricate ornamentation.