In the 19th century, America was the setting for a massive wave of immi-gration that was unique in history During this time, more than 30 Europeanethnic groups came to the Midwestern State of Wisconsion. They broughtwith them a rich Old World architectural legacy that shaped countlessbuildings in the state's rural countryside. These structures reflect a re-markable continuity of life styles, functions, forms, construction methodsand building materials from their homeland across the ocean. As such, theyrepresent a unique American historic resource-but one that is rapidly dis-appearing from the landscape. This paper discusses the cultural continuityand diffusion of traditional building concepts in Wisconsin and the assimila-tion forces that eventully changed folk building methods in the immigrant'snew American environment. The author begins by presenting an overview of his recent research that hasdocumented hundereds of rural ethnic structures. He then discusses theirprimary architectural characteristics, drawing upon examples from select-ed ethnic groups. In shaping these buildings, countless immigrants ex-pressed extraordinary ingenuity, perseverance and ambitions for a brighterfuture. Yet, while seeking a better life in tehir new Wisconsin homeland,they never completely relinquished European ancestral building traditions,and their varied architecture portaryed a myriad of cultural values and re-membered images.Included in this presentation are the Germans, Wisconsin's largest ethnicgroup. Their most unique architectural contribution can be found in theFachwerk construction methods they brought from their fatherland. Thebuildings of the British and Yankees, who generally utilized estabilished-construction features they had learned in the esatern states, are also noted.Central Europeans, including French from Canada who incorporated piecestir place horizontal log construction, and Swiss and Austrian immigrantswho erected distinctive stone structures, are then discussed. From Europe'sLow Countries, Luxembourgers and Belgians replicated Old World buildingsusing stone and brick. Settlers from the Nordic Countries, particularlyNorway and Finland, utilized their wood building skills to erect many typesof low structures . The Bohemians left a sizable legacy of traditional struc-tures, but folk buildings of other Eastern European immigrant groups arerare because they quickly adopted new American building techniques. None-theless, several remarkable structures built by Poles, Russians, Estoniansand Uthuanlans have been found in the state.The paper then addresses how, over time, changing attitudes and conditionsresulted in adapta tions of traditional building methods and the assimilationof new values and ideas. It notes why, in some cases, changes occurred slow-ly in some ethnic settlements, while others quickly rejected their tradi-tional ways in favor or new American techniques. Thus the study offers in-sights into suchquestions as the transfer of tradtional building techniquesover time and space, the adaptations made when new conditions confrontedfolk builders, and the reasons why some early structures and other elementsof the built landscape have survived to the present day. These questions arenot only important to scholars of folk material culture, they are also crucialto understanding how we can better manage these historic resources for thefuture.