King Peter I of Serbia was born on June 11, 1844, and became the ruler of Serbia in 1903. He was a member of the House of Karađorđević and played a significant role in modernizing the country. His reign saw the establishment of a constitutional monarchy and significant social reforms. During his rule, King Peter I focused on improving education and infrastructure, which helped Serbia grow economically. He was also known for his commitment to the Serbian people and their rights. He ruled until his death on August 16, 1921, leaving a lasting legacy in Serbian history.