Charlton, John (d. 1353), lord of Powys, soldier, and administrator, was the son of Robert Charlton of Shropshire (d. 1300). He came into possession of his inheritance in 1306 and in 1307 acted as proxy for the men of Salop in the Carlisle parliament. He was a member of Edward II's household and was knighted in 1308. The first episode of his Irish career was brief. In 1309 he was sent to Ireland, but on 25 June that year Gruffudd ab Owain, lord of Powys, died, and Charlton was recalled to serve on the Welsh marches. The king granted him permission to marry Hawise de la Pole, Gruffudd's sister, and on 26 August he received the livery of the castle of Welshpool as well as the domains and rights of Gruffudd ab Owain.
In 1310 Charlton again proved his loyalty to the king by raising 400 troops for an abortive expedition against the Scots; around that time Edward made him his chamberlain. But as Edward's fortunes declined, so did Charlton's. In 1318 he was replaced as chamberlain by the younger Hugh Despenser, which undermined his loyalty to the king. He faced a prolonged challenge to his lordship over Powys from his wife's uncle, Gruffudd de la Pole, who held the lands to be his through descent, and the two were involved in a violent struggle throughout the 1310s. As a prominent English lord on the Welsh marches, Charlton engaged in constant campaigns to protect his rights against rivals and to subdue disorder in his lands.
In 1337 Charlton was appointed justiciar of Ireland, a role for which his experience of fighting the Welsh admirably fitted him. He was summoned before the king's council on 29 June to take instruction for the Irish mission, and on 26 July ships were ordered for his crossing. He faced a daunting task in Ireland, as the colony seemed at times to be verging on collapse; in particular the Dublin administration had come under extreme pressure from Leinster. To aid him in his task of resuming control in Ireland, he was granted 1,000 marks in cash and accompanied by a number of associates, including his brother Bishop Thomas Charlton (qv) of Hereford, who was appointed chancellor of Ireland, and a force of 200 Welsh archers. The Charltons and their entourage landed in Ireland on 14 October. But in spite of these elaborate arrangements, the new justiciarship soon ended in acrimony. By 15 May 1338 Charlton had been removed from his position as a result of charges probably relating to financial mismanagement of government funds; prominent among his critics was his brother, who was then appointed custos of the Irish lordship. Charlton left Ireland for England in June. Thereafter his health declined and he died in 1353.