The ICUN was started in 1948 in France. The initiative was started by UNESCO and pushed by biologist Julian Huxley. It was the first and only organization to support animals in need of conservation at is time. The ICUN started off with 66 members; at the Conference on the Protection of Nature, they drafted the first list of endangered species. 

The ICUN’s most famous article “The Red Data Book” was drafted in 1964. The Red Data Book included a list of the global status of biological species. It provides vital information regarding the status of these organisms. 

After being involved in the Stockholm’s United Nation Conference on the Human Environment, the ICUN spearheaded three international conferences: the Convention on International Trade in Endangered Species of Wild Fauna and Flora, Convention of Wetlands of International Importance, and Convention Concerning the Protection of World Cultural Heritage. 

In 1975, the ICUN started working on the World Conservation Strategy, which gave an idea about the newer strategies to keep ecosystems intact. In this period of time, the ICUN worked with the Worldwide Wildlife Federation. 

In 1982, the ICUN started the Conservation for Development Centre, which allowed conservation projects to occur in 30 countries. The ICUN + the WWF + the UNEP published Caring For the Earth. The ICUN started to focus in the social conservation side. 

Today, the ICUN has passed 300+ resolutions focusing on economic practices related to conservation. In 1990, the ICUN changed their name to the World Conservation Union while continuing to use ICUN as the abbreviated form. The ICUN identifies the following as their point of focus - “business, climate change, economics, ecosystems, environmental law, forest conservation, gender, global policy, marine and polar, protected areas, science and knowledge, social policy, species, water and world heritage.”