alternatehistory.com

Throughout the 19th century Ottoman Empire lost almost all of its territory in Europe. However, it hung onto Arab lands in Middle East until the final dissolution of the empire.

Your challenge is to reverse this: with as late a POD as possible (preferably one after January 1, 1800) have the Ottomans loose their possessions in Arabia and Middle East by the 20th century but manage to retain its territories in the Balkans.
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