The Eighteenth Century has been a century in which changes were experienced in every field in the world and especially in Europe, and the balance of power began to change. Military, social and economic changes in Europe caused the emergence of new empires and the weakening of the powerful empires of the period that could not adapt to this change. The subject of our book, Peter the Great, who founded the Great Russian Empire that marked this period, and Frederick the Great, who is referred to as the founder of the Prussian state, made their countries competitive with other European states in every field, and set an example for many countries. In this study The Eighteenth Century In order to understand how the Ottoman Empire, which is still one of the strongest empires of the century, followed the developments taking place around it, we tried to examine how the reforms of these two great leaders in their countries found their place in the contemporary Ottoman sources of the period.