He was martyred, I think.
However, that has nothing to do with my legend.

About the founding of the city of Venice--say four hundred and fifty years after Christ--( for Venice is much younger than any other Italian city,) a priest dreamed that an angel told him that until the remains of St.Mark were brought to Venice, the city could never rise to high distinction among the nations; that the body must be captured, brought to the city, and a magnificent church built over it; and that if ever the Venetians allowed the Saint to be removed from his new resting-place, in that day Venice would perish from off the face of the earth.

The priest proclaimed his dream, and forthwith Venice set about procuring the corpse of St.Mark.

One expedition after another tried and failed, but the project was never abandoned during four hundred years.

At last it was secured by stratagem, in the year eight hundred and something.