The thesis provides an historical view of the American Lutheran Church in Oslo. It analyzes its nature as an ethnic institution and presents a study of the correlation between ethnic and religious identity among the respondents. The work is done on the background of what scholars have said about immigrant churches in the US, as well as immigrant groups religious institutions within Norway. The particular historiographic point of interest is the balance between immigrants' old identity from the homeland, culturally and religiously, and the identity acquired through interaction with American or Norwegian mainstream society. In order to examine the ethnic and religious identity in the ALC, I have compared it with two contemporary Norwegian Lutheran churches in the US. To clarify the picture of the ALC as an international and interdenominational church, I have studied it both from a pastor's perspective and from members perspective, using in-depth interviews, questionnaires and church archive materials. The main focus is on the ethnic and religious identity of the people included in the survey. One of the main conclusions is that there is a constant interaction between ethnicity and faith.