The icon depicts the translation (movement) of the relics of Saint Nicholas from Myra (in present-day Turkey) to Bari, on the Italian Peninsula, to save them from the Turks, who were persecuting Christians and destroying churches and holy objects.
Saint Nicholas of Myra (270 - 343), was a historic 4th-century Saint and Greek Bishop of Myra. Because of the many miracles attributed to his intercession, he is also known as Nikolas the Wonderworker. He had a reputation for secret gift-giving, such as putting coins in the shoes of those who left them out for him and thus became the model for Santa Claus. His reputation evolved among the faithful, as was common for early Christian saints.
Rare iconography!