**5. “Christian socialism” and the 20th-century context (the lineage leading to liberation theology)**

In the 20th century, this current crystallized into concrete intellectual movements such as “Christian socialism” in Europe, America, and Japan, and later “liberation theology” in Latin America.

- Dialectical theologians such as Karl Barth were involved in socialist movements in their early years and were called “red pastors.”
- Leading 20th-century American liberal theologians such as Reinhold Niebuhr also extensively incorporated Marxist class analysis in their early construction of social ethics.

**Summary**

Liberal theology (especially reformist and democratic denominations such as Congregationalism) accepted Marxism not because it accepted materialism or atheism as they were.

Rather, it was the result of the convergence of theological and historical demands:

- Prioritizing this-worldly ethics and social reform over doctrine (dogma)
- Evaluating Marxist “class analysis” and “structural criticism” as tools for realizing Christian justice and love on earth
- Compatibility with the system-critical and democratic social-construction spirit unique to Congregationalism