Part of the "Treaty Series" of coins, this is a reference to the Treaty of Bretigni, signed between England and France on May 8, 1360. It was negotiated because of the continued successes of Edward III in his continental wars. Among many other territorial points agreed, the English renounced their pretensions to the crown of France. This affected the king's titles as shown on the coinage. On previous coins the king's titles were "Edward, By the Grace of God of England, France, and Ireland King." Now they read, "Edward, by the Grace of God of England and Ireland, King, Duke of Aquitaine." The treaty was later broken and on the "post-treaty" period nobles the title of King of France was resumed.