One way the ottomans conquered a large empire was by using loyal, well-trained soldiers called

Ottoman Empire used loyal, well-trained soldiers called Janissary to conquer large empire. They were non-Muslim boys subjected to severe discipline and converted to Islam. The result of their uprising was that they were extremely well-disciplined troops, and became members of the askeri class, the first-class citizens or military class. They were prohibited from growing a beard, taking up a skill other than soldiering, and marrying.