Before becoming Speaker, de la Mare worked as a toll collector, was
Sheriff of Herefordshire in 1374, and served as a steward to
Edmund Mortimer, 3rd Earl of March. It may have been his connection with Mortimer which led to his election to Parliament. De la Mare attended the
Good Parliament in 1376 as a
knight of the shire for
Herefordshire. After being elected as Speaker, he served as a spokesman for the
House of Commons in the
House of Lords during the indictment of various figures close to
King Edward III, including the king's mistress
Alice Perrers, who was accused of having gained an undue degree of influence over the king. However, the political influence of the Good Parliament was brief. In November 1376, de la Mare was imprisoned in
Nottingham Castle by
John of Gaunt. Despite pleas for his release, the
Bad Parliament of 1377 refused to pardon him. However, he regained his freedom in June 1377, following the death of Edward III. Following his release, Mare was pardoned and compensated by
King Richard II. He was re-elected as Speaker of the Commons in the Parliament of October 1377. Peter de la Mare served in several more Parliaments during the 1380s. The last recorded mention of him was as a
feoffee to Richard Burley in 1387. ==In
Piers Plowman==