You wouldn't think that there would be so many men named Zosimus, much less that so many of them would be saints. There doesn't seem to be a great deal of information about any of them, so I will attempt to give a brief overview of them all here.
We don't know when he was born. He was probably Greek, and may have been of Jewish descent - his father's name was Abram. He was elected Pope after the death of Innocent I, having been recommended by
John Chrysostom. Pope Zosimus reigned from
417-18 - a whole year! During his time as Pope, he formally condemned
the Pelagian heresy. Innocent I had condemned it too,
but the heresy was so appealing in its denial of original sin that
it just wouldn't go away.
Zosimus also worked to expand papal supremacy, but was not very
successful due to personality clashes with local bishops. Several
letters written by him survive, as well as a Decree ordering priests
to stay out of taverns. Pope Zosimus died in Rome on December 27,
418. He was apparently much disliked in Rome, and his passing was
cause for celebrations in the streets.
Zosimus of Palestine
This Zosimus was a hermit who lived on the banks of the Jordan
River in the fifth century. He is remembered for his discovery of
Saint Mary of Egypt (the story of which is beautifully detailed by Ceallach in that writeup), and for the writing of her biography.
Zosimus of Syracuse
Zosimus of Syracuse was born around 570, somewhere in Sicily. When he
was only 7 years old, he was placed by his wealthy parents in a
monastery near Syracuse. At the monastery, he was charged with the
task of watching over the relics of Santa
Lucia. How boring! He ran away from the monastery, but his parents
sent him back in disgrace. Soon thereafter, he had a vision of Santa
Lucia. She seemed angry at him, but was appeased by Mary and accepted
his promise to do better in the future.
After that, he settled down and served as a monk for thirty years
before being elected as abbot of the monastery. In 649, he was made
the reluctant bishop of Syracuse and became widely known for his
care of the poor and his educational programs. He remained the bishop
until his death at the age of 90.
There were several martyrs named Zosimus. The first, a citizen of
Antioch, died in 107 with Saint Rufus during the reign of
Trajan after being thrown to the beasts in the arena.
The next Saint Zosimus was martyred three years later in Umbria,
Italy, also on Trajan's watch.
And finally, in 303, yet another Zosimus was executed during the persecutions of Emperor Diocletian, this time with a Saint Athanasius.