This stamp was issued by the Princely State of Dewas under the Central India Agency (Malwa Agency) during the British rule.
When we talk about stamps we always presume it is used for postage or mailing. However, stamps are also used for different purpose like revenue or fees collection across the globe as you have read before. War can be an expensive affair and to sustain this kind of situation funds are necessary. But the direct impacts of war are on the common people who have to pay increased revenue collection to support the war expenses.
This stamp is not used for postage but for revenue collection to raise funds and to pay war expenses during World War I and II. The princely state of Dewas was under British rule and sided with Great Britain during the war. To support the war funds these kinds of stamps were printed by Dewas.
The princely state of Banganapally Chhatarpur, Dewas Junior and Jhalawar issued this type of war fund revenues stamps.
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