Iamblichus was a philosopher of the late Roman Imperial period, active around 245 to 325 CE. He is a major figure in the Neoplatonist school, a philosophical tradition that developed centuries after the Classical Greek era. He led an important school in Apamea, Syria.

His surviving works are primarily philosophical treatises. These include On the Pythagorean Life, The Exhortation to Philosophy, and several texts on mathematics and arithmetic, such as On the Arithmetic of Nicomachus. A number of his other writings are lost or survive only in fragments.

According to modern scholars, Iamblichus's significance lies in his systematic organization of late Platonic thought. He is particularly noted for his deep engagement with Pythagorean philosophy and for his influential efforts to integrate traditional religious ritual, known as theurgy, into philosophical practice. His work had a profound impact on the later development of Neoplatonism, especially on thinkers like Proclus.