French Colonies. (Camerouns). 1940. Air Mail envelope addressed to France bearing Yvert 217, 40c blue and Yvert 219, 60c turquoise tied by Doula/ Cameroun date stamp '20th Oct 40', endorsed 'via Victoria/ via Great Britain' with 'Controle Postal Militaire' label tied by oval 'Ouvert/ Par/ L'Autorite Militaire' on face and reverse with circular 'A/ 5' cachet and instructional hand-stamp 'Retour a L' Envoyeur/ Relations Postales/ Interrompus' struck twice in violet on face.
Germany had begun the Occupation of France on 22nd June 1940 so the mail service was suspended.