Charles Brandon, 1st Duke of Suffolk (c. 1484 – 22 August 1545) was an English military leader and courtier. Through his third wife, Mary Tudor, he was the brother-in-law of King Henry VIII.

Born in 1484, Charles Brandon was the second but only surviving son of Sir William Brandon, Henry Tudor's standard-bearer at the Battle of Bosworth Field. William Brandon was killed during the battle. Charles Brandon's mother, Elizabeth Bruyn (d. March 1494), was the daughter and co-heiress of Sir Henry Bruyn (died 1461).

Charles Brandon was brought up at the court of Henry VII, and became Henry VIII's closest friend. He was about seven years older than Henry and was a role model for the young prince, especially after the death of his brother, Prince Arthur. Brandon was becoming an excellent jouster and a ladies' man and as such was an object of admiration for Henry. Brandon is described by Dugdale as "a person comely of stature, high of courage and conformity of disposition to King Henry VIII, with whom he became a great favourite." Brandon held a succession of offices in the royal household, becoming Master of the Horse in 1513, and received many valuable grants of land. On 15 May, he was created Viscount Lisle, having entered into a marriage contract with his eight-year-old ward, Elizabeth Grey, suo jure Viscountess Lisle. The contract was ended and the title was forfeited as a result of Brandon's marriage to Mary Tudor in 1515.

He distinguished himself at the sieges of Thérouanne and Tournai in the French campaign of 1513. One of the agents of Margaret of Savoy, governor of the Netherlands, reminded her that Brandon was a "second king" and advised her to write him a pleasant letter. At this time, Henry VIII was secretly urging Margaret to marry Lisle, whom he created Duke of Suffolk on 4 March 1514, although he was careful to disclaim any complicity in the project to her father, Maximilian I, Holy Roman Emperor. When Brandon was made Duke of Suffolk, there were only two other dukes in the kingdom (Buckingham and Norfolk). After being made Duke of Suffolk, he continued to travel around that county so as to get to know the towns and villages and the local dignitaries. He mainly stayed at his family's homes, including Wingfield Castle and the now demolished Henham Hall.

After his marriage to Mary, Suffolk lived at Westhorpe Hall for some years in semi-retirement, but he was present at the Field of the Cloth of Gold in 1520, an event organised in part by his cousins, Sir Richard Wingfield who was English ambassador to France and Thomas Wolsey who was Cardinal and Lord Chancellor.

In 1523 he was sent to Calais to command the English troops there. He invaded France in company with Floris d'Egmont, Count of Buren, who was at the head of the Flemish troops, and laid waste the north of France, but disbanded his troops at the approach of winter.

Brandon was appointed Earl Marshal of England in 1524, a position previously held by Thomas Howard, 2nd Duke of Norfolk. However, in 1533 he relinquished the office to Thomas Howard, 3rd Duke of Norfolk, "whose auncesto[ur]s of longe tyme hadde the same until nowe of late."

After Wolsey's disgrace, Suffolk's influence increased. He was sent with Thomas Howard, 3rd Duke of Norfolk, to demand the Great Seal from Wolsey (it is possible Henry sent Brandon to Wolsey as they were related); and Suffolk acted as High Steward at the new Queen's coronation. He was one of the commissioners appointed by Henry to dismiss Catherine's household, a task he found distasteful.