Kirchenkampf (English: "church struggle") is a German term pertaining to the situation of the Christian churches in Germany during the Nazi period (1933–1945). Sometimes used ambiguously, the term may refer to one or more of the following different "church struggles": the internal dispute between the German Christians (Deutsche Christen) and the Confessing Church (Bekennende Kirche) over control of the Protestant churches; the battle between the Nazi regime and the Protestant church bodies; and the battle between the Nazi regime and the Roman Catholic Church. Around two thirds of Germans were Protestant, and one third Catholic when the Nazis took power. Many historians maintain that Hitler's goal in the Kirchenkampf entailed not only ideological struggle, but ultimately the eradication of the churches. Other historians maintain no such plan existed. The Salvation Army, Christian Saints and the Seventh-day Adventist Church all disappeared from Germany during the Nazi era.
Nazi ideology was hostile to traditional Christianity in various respects and the Nazi Party saw the Church Struggle as an important ideological battleground. Hitler biographer Ian Kershaw wrote of the Struggle in terms of an ongoing and escalating conflict between the Nazi state and the Christian churches. Historian Susannah Heschel wrote that the Kirchenkampf refers only to an internal dispute between members of the Confessing Church and members of the (Nazi-backed) "German Christians' over control of the Protestant church. Pierre Aycoberry wrote that for Catholics the phrase kirchenkampf was reminiscent of the kulturkampf of Otto von Bismarck's time - a campaign which had sought to destroy the influence of Catholicism in majority Protestant Germany.