In his youth he accompanied his father to the marriage of Princess Mary, to King Louis XII of France. He returned to France during the 1520s, fighting with distinction around Calais. In July 1523 after the taking of Morlaix, he was invested as a Knight by Thomas Howard, Earl of Surrey and succeeded to his father's title in November 1529. In 1536 he was one of the 27 peers at the trial of his second cousin Queen Anne Boleyn. After the Dissolution of the Monasteries he acquired much former monastic property. At home he served as a Justice of the Peace for Kent. In 1544 he occupied a high command in the English army which invaded Scotland; later that year he was appointed commanding officer of Calais, a personal possession of the king. He was made a Knight of the Garter on 24 April 1549. Brooke's family were dogged by scandal. His sister, Elizabeth Brooke, was married to Sir Thomas Wyatt but lived openly in adultery with another man. Allegedly she attracted the attention of Henry VIII in 1542, and Eustace Chapuys, the Imperial ambassador, thought that had she tried she could have become Henry's sixth wife. His daughter, Elisabeth Brooke, Marchioness of Northampton, was also prone to scandal as from 1543 she had lived with her future husband William Parr, 1st Marquess of Northampton whilst he was separated from his adulterous wife Anne Bourchier, 7th Baroness Bourchier. They eventually married during the reign of Edward VI, but this was declared invalid by Mary I. In the reign of Elizabeth I, their marriage was finally confirmed as valid. He resigned his post in 1550 and on 23 May became a member of the Privy Council of Edward VI. After Edward's death, Brooke supported the attempt by John Dudley, 1st Duke of Northumberland to place his daughter-in-law Lady Jane Grey on the throne. He was pardoned by Queen Mary I, but subsequently fell under suspicion again. His nephew, Sir Thomas Wyatt the younger was the leader of Wyatt's Rebellion, a Protestant rebellion which brought suspicion on the whole family. Brooke's daughter, Elizabeth Brooke, is thought to have been the instigator of the plot to place Lady Jane Grey on the throne instead of Mary I. During his Rebellion, Wyatt besieged Lord Cobham in Cooling Castle and although Cobham claimed to have resisted, following the failure of the rebellion he was accused of complicity in it and was imprisoned in the Tower of London for a brief period. The next year, at the start of the Roman Catholic Queen's formal reconciliation with the Holy See, he was assigned to welcome to England the papal legateCardinal Pole, who went on to be responsible for many Protestant martyrdoms in England. The entertainment is recorded as having taken place at Cooling Castle in 1555. Thereafter Cobham limited himself to local affairs in Kent.
Marriage and issue
In about 1517, certainly before 1526, at Eaton Bray in Bedfordshire, he married Anne Braye, eldest daughter and co-heiress of Edmund Braye, 1st Baron Braye, of Eaton Bray, by his heiress wife Jane Halliwell. By his wife he had issue ten sons and four daughters:
Sons
William Brooke, 10th Baron Cobham, eldest son and heir, who married firstly, Dorothy Nevill, by whom he had one daughter, and secondly in 1560, Frances Newton, a Lady of the Bedchamber to Queen Elizabeth I, by whom he had seven children.
George Brooke, who married Christiana Duke, only daughter and sole heiress of Richard Duke, MP, of Otterton, Devon, by whom he had issue:
*Duke Brooke;
*Peter Brooke;
Thomas Brooke, alias "Thomas Cobham", MP, married and had issue.
John Brooke, alias "John Cobham", who before 1561 married Lady Alice Norton, widow of Sir John Norton of Northwood, Milton, Kent, without issue.
Sir Henry Brooke, who married Anne Sutton, a daughter of Sir Henry Sutton of Nottinghamshire, by whom he had issue:
