A safari jacket or bush jacket is a garment originally designed for the purpose of going on safari in the African bush. Similar lightweight, light-coloured uniforms were also worn by European soldiers serving in warm climates from the 19th century and, little altered, throughout World War II. They typically featured epaulettes, pleated pockets, belts..etc
In 1936, author and adventurer Ernest Hemingway designed a 'bush jacket' which was made by Willis & Geiger. And in the 1960s and 1970s safari suits became fashionable thanks to designers versions for men and women by, for example, French designers Ted Lapidus and Yves Saint Laurent.
Sources : Wikipedia