In his treatise Perpetual Peace, he wrote that all countries should unite in a league of the nations, which would assure peaceful coexistence between nations. About 125 years after the appearance of this treatise in 1795, the League of Nations was founded, after the First World War. After the Second World War it was replaced by the United Nations. So you could say that Kant was the father of the UN idea. Kant’s point was that man’s “practical reason” requires the nations to emerge from their wild state of nature which creates wars, and contract to keep the peace.
