What are 5 accomplishments of emporer Constantine the great?

Emperor Constantine the Great is renowned for several significant accomplishments: he enacted the Edict of Milan in 313 AD, granting religious tolerance throughout the Roman Empire, particularly benefiting Christians. He founded the city of Constantinople (modern-day Istanbul) in 330 AD, which became a major cultural and economic center. Constantine also restructured the empire's administration and military, strengthening its governance and defense. Additionally, he convened the First Council of Nicaea in 325 AD, which addressed key theological disputes and helped unify Christianity.