**[Google Gemini]**
The background to why the Protestant Congregationalist (Kumiai Kyokai) tradition and modern liberal theology approached and absorbed Marxist/communist theory and social analysis lies in strong affinities and structural factors in the realms of intellectual history, theology, and organizational structure.

Christianity itself (particularly the official principles of mission schools, etc.) did not officially accept the atheism or materialist conception of history of Marxist communism.

However, from the late 19th century to the mid-20th century, a strong movement emerged on the side of Protestant liberal theology to approach Marxism and incorporate its social criticism.

The main background and reasons can be organized into the following five points.

**1. The “Social Gospel” movement and the realization of the Kingdom of God on earth**

In the latter half of the 19th century, as the Industrial Revolution advanced, poverty, labor problems, and urban class divisions became severe. In response, liberal theologians centered in American Congregationalist and Baptist circles launched the “Social Gospel” movement.

- Pursuit of justice on earth:
Whereas traditional orthodox theology emphasized “the salvation of the individual soul through personal faith (salvation in the afterlife),” liberal theology set as its theological goal “the transformation of the social structure of this world itself through the love and justice of Christ.”