Maria Olivera Lazarević, also known as Despina Hatun, was a Serbian princess and consort of the Ottoman sultan Bayezid I, whom she married just after the Battle of Kosovo in 1389 as a pledge of peace between the Lazarević and Ottoman dynasties. She was the youngest daughter of Lazar of Serbia and Princess Milica.

Bayezid I, also known as Bayezid the Thunderbolt, was the sultan of the Ottoman Empire from 1389 to 1402. He adopted the title of Sultan-i Rûm, Rûm being the Arabic name for the Eastern Roman Empire. In 1394, Bayezid unsuccessfully besieged Constantinople. Bayezid vanquished all the Beyliks and proceeded to conquer and vassalize the entirety of Anatolia. In 1402, he once more besieged Constantinople, appearing to find success, but he ultimately withdrew due to the invasion of the Mongol conqueror Timur. He defeated the Crusaders at the Battle of Nicopolis in what is now Bulgaria in 1396. He was later defeated and captured by Timur at the Battle of Ankara in 1402 and died in captivity in March 1403, which triggered the Ottoman Interregnum.