Postage stamps were first issued by Great Britain in 1840 to regularize the payment of fees for letters sent through the postal system. Within a few years most European powers had issued stamps of their own. The Ottoman Empire was a late entry on January 1, 1863 with a stamp centered around the Tughra, the Turkish emblem of sovereignty and seal of the current sultan Abdülaziz I. Below the seal was an inverted crescent bearing the inscription "Devleti Aliye Osmaniye," or "The Sublime Ottoman Empire" in Turkish-Arabic script. Hilal, the very slight crescent moon visible after the new moon, was iconic in Islamic cultures as the hallmark of their lunar month.
The Arabic calligraphy of the Tughra is quite complex.