He was appointed to the embassy charged with concluding peace with France in 1492, and again in 1500 he formed one of the suites which accompanied Henry VII to Calais to meet the Archduke Philip of Austria. In 1503, together with Nicholas West, he was given the mission of concluding a treaty with the Emperor Maximilian at Antwerp. The main object of this treaty was to induce Maximilian to withdraw his support from Edmund de la Pole, 3rd Duke of Suffolk, and banish him and the other English rebels from his dominions. Other points touched upon were the treatment of Milan and the question of Maximilian receiving the Order of the Garter. Maximilian was indecisive and allowed the English ambassadors to leave.
On his return to England, Brandon was given offices, including master of the king's horse. He was noted for his prowess as a knight and his skill in military affairs. In the records of a tournament held in 1494 to celebrate the creation of the Prince Henry as Knight of the Bath and Duke of York, Brandon is mentioned as having distinguished himself. He was made a Knight of the Garter.
In October 1507 he was sent to meet Balthasar de Castiglione, ambassador for the Duke of Urbino, who came to England to receive the Garter for his master. Brandon died on 27 January 1510.[3]
Brandon married secondly, Elizabeth Dynham (died 19 October 1516),[5] widow of Fulk Bourchier, 10th Baron FitzWarin (25 October 1445 – 18 September 1479) and of Sir John Sapcote (died 1501) of Elton, Huntingdonshire. She was the daughter of Sir John Dinham (1406–1458) by Joan Arches (died 1497), and the sister and coheir of John Dynham, 1st Baron Dynham (died 1501).[6] According to Gunn, after Brandon's death his widow, Elizabeth, took a vow of celibacy before Bishop Fisher on 21 April 1510.[3] She died 19 October 1516, and was buried in the Greyfriars, London.[5][7]
Richardson, Douglas (2011). Everingham, Kimball G. (ed.). Magna Carta Ancestry: A Study in Colonial and Medieval Families. Vol. I (2nd ed.). Salt Lake City. p. 282. ISBN978-1449966379.{{cite book}}: CS1 maint: location missing publisher (link)