[Antoninus]

Sulpicius Severus was the first biographer of St. Martin—whom he knew personally. He doesn’t include an account of Martin’s death because he was writing while Martin was still alive. He is the source of the very famous story of Martin, while still a soldier, cutting his military cloak in half and giving half to a naked beggar.

Indeed. I have always found it interesting that some of the greatest saints of that era (Augustine, Martin, Ambrose, Anthony, etc.) have bios written by contemporaries who were close to them personally. They are fascinating historical sources.

[Verginius Rufus]

Of course Augustine was written about by the person who knew him best—himself.