I picked this stamp as it stood out on a crowded page, and only then noticed that it is From This Day in 1971. There you go. Anyway, the World Scout Conference is the organising body of the World Organisation of the Scout Movement; its 1971 conference was held in Tokyo and saw the arrival of Cameroon and (I think) six other nations into the movement. At that time, Cameroon had been independent of French and British colonial governance for about ten years and had undergone some authoritarian, single party measures from its independent leadership. It joined the World Scout Conference in 1971 and hosted the African Cup of Nations in 1972.
https://en.wikipedia.org/wiki/World_Organization_of_the_Scout_Movement
Stamp of the Day 