In 1858, when his career was in decline, he spent two years in Brazil. In Rio de Janeiro, he enjoyed the protection of the emperor Dom Pedro II. He traveled to the rainforests of Espírito Santo and Amazônia, where he extensively depicted native populations. As Araujo explains, Biard was among the very first European painters to meet and depict these populations. In 1862, after returning in France, Biard published the travelogue Deux Années au Brésil with Hachette.
Biard was known as an abolitionist because of the paintings representing the Atlantic slave trade. Yet, historian Ana Lucia Araujo showed that the painter was never an abolitionist His paintings representing the Atlantic slave trade were rather intended to highlight the history of France.