Before Engels wised up, the proposed title of Communist Manifesto was Confession of Faith. As Engels wrote in a letter to Marx in late 1847, before the work’s publication in 1848:
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“Give a little thought to the Confession of Faith. I think we would do best to abandon the catechetical form and call the thing Communist Manifesto.”
Source: Engels, Letter to Marx, November 24, 1847.
Related: Marx and Engels’ The Communist Manifesto, in the Philosophers, Explained series: