Blackbeard is the first foal of Muirin (Born To Sea), a 7f winner at two who finished fourth in the Gr.1 Moyglare Stud Stakes.

Second dam Girouette (Pivotal) won the Gr.3 Phoenix Sprint S. and has three other winners. She is also the second dam of Night Tornado, a Listed winner in France. Her half-siblings include Prince D'Alienor (Verglas), placed in the Gr.3 Prix Messidor, and the Listed-placed Paraphernalia (Dalakhani).

Third dam Vassiana (Anabaa) was Listed-placed and produced six winners from 12 foals. She is a full sister to Villadolide, a Group 3 winner in France, and the Listed winner Victorieux.

Paraphernalia is the dam of Max Vega (Lope De Vega), winner of the Gr.3 John Porter S. and the Gr.3 Zetland S., the Group 2-placed Camphor and the dual Listed-placed Quickstep. This is also the family of the Gr.1 Prix de Diane winner Mrs. Penny (Great Nephew) and the Gr.1 1000 Guineas winner Hatoof (Irish River).

Muirin has a yearling full sister and a colt foal who is a full brother to Blackbeard.