of Scots, to Scotland. He remained with her a year, during which time he made several journeys into England in an attempt to bring about a reconciliation between Mary and Queen Elizabeth. The wise and moderate counsel that he offered to the former were unheeded. In 1562, as a consequence of the civil war in France, he returned there. He was employed against the Protestants in Brittany, was taken prisoner in an engagement with them and sent to Havre, but was soon after exchanged. In the midst of the excited passions of his countrymen, Castelnau, who was a sincere Roman Catholic, maintained a wise self-control and moderation, and by his counsels rendered valuable service to the government. He served at the siege of Rouen, distinguished himself at the battle of Dreux, took Tancarville, and contributed in 1563 to the recapture of Havre from the English. During the next ten years Castelnau was employed in various important missions: first to Queen Elizabeth to negotiate a peace. Castelnau was concerned by the troubles in Scotland at Mary's marriage to Lord Darnley, the Chaseabout Raid, and the murder of David Rizzio. He went to see Mary, Queen of Scots, at Edinburgh Castle in April 1566. She was pregnant. Next he was sent to the Duke of Alba, the new governor of the Netherlands. On this occasion he discovered the project formed by the Prince of Condé and Admiral Coligny to seize and carry off the royal family at Monceaux (1567). After the battle of St. Denis he was again sent to Germany to solicit aid against the Protestants; and on his return he was rewarded for his services with the post of governor of Saint-Dizier and a company of orderlies. At the head of his company he took part in the battles of Jarnac and Moncontour. Ambassador in London In 1572 he was sent to England by Charles IX to allay the excitement created by the St. Bartholomew's Day Massacre, and the same year he was sent to Germany and Switzerland. In September 1575, he was reappointed by Henry III ambassador to Queen Elizabeth, as a successor to Bertrand de Salignac de la Mothe-Fénelon, and he remained at her court for ten years.<ref>John Guy, The Life of Mary, Queen of Scots: My Heart is my Own (Fourth Estate, 2009), p. 450: Frances Yates, John Florio: The Life of an Italian in Shakespeare's England