C.W. Nicol was born in Neath, Wales, and from a young age expressed an interest in wildlife and the environment.

In 1958 he visited the Arctic Circle to research Eider Duck for McGill University, taking up Canadian citizenship. By the early 1960s he was studying karate at JKA, and soon thereafter began to study Japanese at Nihon University.

He then spent two years (1967 to 1969) as a game warden in Ethiopia, setting up the new Semien Mountains National Park for the Ethiopian Government. He returned to Japan, writing a book about his Ethiopian experiences: From the Roof of Africa (1971, ISBN 0 340 14755 5).

Since taking up residence in Japan he has written many books and other literary works. In 1980 he won the Japan Broadcasting Writer's Award for a television drama written in Japanese. He continued to be an active environmentalist, and to this day he travels in Japan and elsewhere giving talks and lectures about the environment, addressing issues such as deforestation and the preservation of natural environments. He is particularly interested in restoring Japan's vast woodlands, and due to these and other endeavours he is well known in Japan.

He now holds Japanese citizenship, which he wrote about in the book Boku ga Nihonjin ni natta riy? ("Why I became Japanese") and he owns a plot of forest land in Japan where he lives.

He has written both fiction and non-fiction in Japanese, including books about whaling (for which he went on a trip on a whaling vessel), books about the environment, and also children's fiction. In 2005, he was awarded an MBE.