"[5] In June 1535, he was in France as a member of the English embassy authorized to negotiate with the French Admiral, Philippe de Chabot.

On 22 December 1541, Howard, his wife, and a number of servants who had been alleged witnesses to the Queen's misconduct were arraigned for misprision of treason, convicted, and sentenced to life imprisonment and loss of goods.

When Lisle's attendance was required in May 1546 at negotiations which resulted in the signing of the Treaty of Ardres on 7 June 1546, he turned command of the English fleet over to Howard.

[11] He was an ally of John Dudley, 1st Duke of Northumberland, then Earl of Warwick, in his coup against the Protector Somerset in October 1549,[12] and on 19 March 1551, received the manor of Effingham, Surrey,[13] and other properties by way of reward.

On 29 October 1552, Northumberland secured Howard's appointment as Lord Deputy and Governor of Calais, and in the same month he was sworn of the Privy Council.

When the young King Edward VI died on 6 July 1553, Howard held Calais for Queen Mary I against the supporters of her rival, Lady Jane Grey.

[14] On 2 January 1554, he was appointed to meet the Spanish ambassadors who had come to London to negotiate a marriage between Queen Mary I and King Philip II of Spain.

[17] Around this date, there was a masque at court, featuring mariners' costumes made of gold and silver cloth, which Francis Yaxley thought was Howard's production.

[22] Howard was compensated by a grant of the reversion of the office of Lord Chamberlain of the Household and an annuity of 200 marks, effective the previous September.

These included lands at Broughton in Buckinghamshire; Billeshurst, Bletchingley, Kingswood, Little Bookham and Tillingdown in Surrey;[24] Lowick in Northamptonshire; Shaw-cum-Donnington in Berkshire; and Tottenham in north London.

In 1566, Howard had some financial difficulties, and handed some of his Surrey estates to his great-nephew Thomas, Duke of Norfolk, retaining Little Bookham for his second wife, Margaret.

[25] After Queen Elizabeth's accession on 17 November 1558, Howard succeeded Edward Hastings as Lord Chamberlain and was appointed to the Privy Council.