He came to Athens at a time when, with the exception of Proclus, there was a great dearth of eminent men in the Neoplatonist school. It was for this reason rather than for any striking ability of his own that he succeeded to the headship of the school on the death of Proclus in 485.
During this period, the professors of the old Greek religion suffered persecution at the hands of the Christians and Marinus was compelled to seek refuge at Epidaurus.
His chief work was a biography of Proclus, the chief source of information on Proclus' life. The publication of the biography is fixed by internal evidence to the year of Proclus's death; for he mentions an eclipse which will happen when the first year after that event is completed. It was first published with the works of Marcus Aurelius in 1559; it was republished separately by Fabricius at Hamburg in 1700, and re-edited in 1814 by Boissonade with emendations and notes. He is also the author of a commentary on the Data of Euclid.
Other philosophical works are attributed to him, including commentaries on Aristotle and on the Philebus. It is said that he destroyed the latter because Isidore, his successor, expressed disapproval of it. Marinus died in 500 AD, possibly in Athens.
^O'Connor J.J. and Robertson E.F. "Marinus of Neapolis". School of Mathematics and Statistics University of St. Andrews, Scotland. April 1999. Accessed: November 22, 2008. "Marinus of Neapolis was probably a Samaritan, but just possibly a Jew. He became a convert to the Greek way of life and joined the Academy in Athens where he was a pupil of Proclus who was head of the Academy. In fact when Proclus wrote a commentary on the Myth of Er, he dedicated it to Marinus."