Zazpiak Bat is a motto attributed to Basque explorer Antoine-Thomson d'Abbadie in the nineteenth century, from the Basque words zazpiak meaning 'the seven' and bat meaning 'one', translates as "the seven [are] one" and refers to the seven Basque Country traditional provinces. The motto is based on a similar one fashioned by the Enlightenment society Real Sociedad Bascongada de Amigos del País in 1765, Irurac bat ("the three [are] one", after the provinces currently making up the Basque Autonomous Community), while a like variant was created too in the 19th century known as "Laurak bat" ("the four [are] one", after the four Basque provinces of Spain).
Zazpiak Bat is also a heraldic nickname for the Basque coat of arms which includes the arms of the seven provinces mentioned, stressing their unity. It was designed by Jean Jaugain in 1897 for the Congrès et Fêtes de la Tradition basque celebrated at Saint-Jean-de-Luz.
The original Zazpiak Bat features a design of traditional arms of six Basque territories, namely Álava, Guipúzcoa, and Biscay (the three which make the Basque Autonomous Community) plus Navarre (both in Spain); and the two that are part of the French department of the Pyrénées Atlantiques - Zuberoa and Lapurdi. The coat of arms of the third traditional province, Lower Navarre, as the version it is of the coat of arms of the Kingdom of Navarre, is omitted and represented by the latter. The modern design is based on the current simplified heraldry of these territories.
Laurak Bat with the four Basque provinces in Spain (Navarre originally included, but blanked with a red field following protests from the Navarrese government and a subsequent court decision for its removal) was adopted as the coat of arms of the Basque autonomous community.