Brewes’s early life is obscure. There are no references to him prior to September 1430 when he was elected as one of jurats who governed Dover and it is likely that his sudden appearance among the governing elite resulted from a marriage into a Portsman’s family. During this first year as a jurat Brewes was also elected to his first Parliament, which assembled at Westminster on 12 Jan. 1431. Along with the experienced parliamentarian, John Braban*, Brewes spent only 25 days in the Commons before passing over the representation of Dover to New Romney’s baron, John Adam*, who remained there until the Parliament’s close. Brewes received only 45s. of the 78s. 4d. due to him immediately and the outstanding debt was not settled until the eve of his departure for his second Parliament in 1437.
On his return from the 1431 Parliament Brewes continued to be involved in the government of Dover and the wider administration of the Cinque Ports. From then until April 1439 he represented Dover at nine meetings of the Brodhull,
In January 1437 Brewes travelled to Westminster for his second Parliament. On this occasion he sat alongside Walter Nesham*, the long-serving bailiff of Dover. It is impossible to be sure how long Brewes or his fellow baron sat in this Parliament. In 1436-7 Brewes was paid 53s. 4d. for parliamentary wages, while the following year a debt ‘of Parliament the previous year’ of £6 13s. 4d. was recorded as owing to him.
Little evidence survives of Brewes’s private affairs. He was resident in Shipman ward in Dover, where he paid maltolts, and by 1434 he was one of the four constables of that ward.
