So, the sailors would say that if you died at sea, the swallows would fetch your soul and deliver it to heaven, but from another text:

“Sailors wore swallow tattoos not only as a symbol of how many miles they had traveled, but as a lucky charm. Because the swallow always returns home, a tattoo of a swallow was a good luck charm that would bring the sailor home to his family. Because of this meaning, swallow tattoos have also become popular with soldiers as a lucky charm to bring the soldier home to his or her family and friends.”

For me… a reminder for those times I feel lost at sea and very far from home.