He was a Yoruba Born African photographer noted for his involvement in the campaign against inhumane abuses in the Congo Free State.

He taught in a Lagos Primary School for a few years. However, in 1884, he joined the Congo Free State’s colonial service as a clerk, eventually ascending to the post of district sub-commissioner and French-English translator in the governor-office general’s in Boma. He established himself in Boma, the capital at the time, and operated a general store and photographic studio.
In 1900, the colonial authorities hired him to assist suppress rebellion among West African Force Publique members.
In 1894, he traveled to Antwerp to attend the Internationale Exposition d’Anvers. Some of his images were featured in the journal Le Congo Illustré. In 1900, he proved his devotion to the Congo Free State by siding with the government during a revolt by the Force Publique.
Shanu sent information on the maltreatment of West African laborers in the Congo to British Consul Roger Casement in 1903, who introduced him to Edmund Morel and the Congo Reform Association, which worked to eradicate slavery and other humanitarian atrocities in the Congo Free State. For several years, Morel and Shanu communicated, with Shanu sharing transcripts of cases against low-ranking Congo Free State officials, which proved to be particularly illuminating.
Shanu was discovered while attempting to obtain information from the police head of Boma, and as a result was harassed by state officials. After it was revealed that Shanu had furnished the Congo Reform Association with proof of crimes in the Congo, government personnel were publicly advised to boycott his companies. Shanu committed suicide in July 1905, because his business was destroyed and himself in despair.