but during the fifteenth century it was not an issue yet because their numbers were still growing and would continue to grow in order to boost their elite power. A man by the name of Konstantin Mihalovic was captured by the Turks in 1455 and would eventually write a memoir about his time with the Ottoman Empire Janissary units. His account would be considered flawed because of the translations from Serbian to Czech and Polish. There is no original text from his memoir and only translations are left to work from, and those have far fetched ideas of what the Janissaries were doing during the time. He was recaptured in 1463 by Hungarian troops and eventually wrote the memoir after he became a Christian again. His memoir is an important piece of history, but scholars and historians have widely debated the authentic nature of his stories and doubt the consistency of his tales. The Ottoman Empire was one of the first states to put gunpowder weapons into widespread use. The famous Janissary corps of the Ottoman army began using matchlock muskets as early as the 1440s. The army of Mehmed the Conqueror, which conquered Constantinople in 1453, included both artillery and foot soldiers armed with gunpowder weapons. The Ottomans brought to the siege sixty-nine guns in fifteen separate batteries and trained them at the walls of the city. The barrage of Ottoman cannon fire lasted forty days, and they are estimated to have fired 19,320 times. 16th century The 16th century saw the first widespread use of the matchlock musket as a decisive weapon on the battlefield with the Turks becoming leaders in this regard. The first of these campaigns was the campaign against the Persians in 1514 under Yavuz Sultan Selim, or Selim the Grim. Armed with gunpowder weapons, his army defeated the Persians at the Battle of Chaldiran. After his victory over the Safavids, Selim turned his attention towards the Mamluk dynasty in Egypt. The decisive battle of his campaign against the Mamluks, and the battle which highlighted the importance of the musket in the Ottoman military, was the Battle of Raydaniyah, fought in 1517. There, Selim outflanked the entrenched Mamluk artillery, and attacked the Mamluk forces with his Janissaries. The Janissaries, armed with firearms, destroyed the Mamluk army, armed mostly with traditional swords and javelins. Reference was made by João de Barros to a sea battle outside