 After the Mongol invasion, across the Muslim world, in the 13th century, the curved designs became more popular in particular with the Ottomans in Anatolia.The Ottomans continued to use curved swords, developing them further until they distinguished a distinct heavy-bladed version which would become the Kilij in the first half of the 15th Century.The Mongol style sabers continued to remain in use in Persia until the late 16th century, at which point they developed into the recognizable Shamshir.