One of the most diligent and successful administrators to represent Northumberland in the Middle Ages, John Mitford pursued a career as remarkable for its length as its involvement in almost every facet of local government. Over a period of almost 40 years he not only sat in at least 13 Parliaments, but also served as a tax collector, crown commissioner, escheator, sheriff, alnager, j.p. and diplomat, while also holding a variety of stewardships and constableships for such eminent figures as Henry, earl of Northumberland, Edward, duke of York, and Sir John le Scrope. His achievements were largely those of a self-made man, although his family was not without influence, especially in the port of Newcastle-upon-Tyne, where his father held office in the 1350s as a collector of customs and pesager of wool. One of his kinsmen, also named John Mitford, belonged to the household of Edward, the Black Prince, who employed him, in 1352, to ship grain from Newcastle to London. This John owned a tenement in the City and may well have helped his young relative and namesake to obtain a legal training there. For the subject of this biography was almost certainly a lawyer, with a rapidly growing circle of clients in the north. Besides premises in Newcastle, Gilbert Mitford, John’s father, owned a small estate at Bolam; and in 1364 John himself acquired other property a few miles to the east in Mitford, near Morpeth. Further expansion followed five years later, when David, earl of Atholl, granted him ‘all his lands and tenements in the vill of Molesden’ in Mitford, thus providing him with a sizeable territorial base. It was perhaps also at this time that the earl settled upon John and his brother, Alexander, additional holdings in the Lincolnshire village of Gainsborough, which John passed on to his descendants.
In February 1370, Henry, Lord Percy, made John steward of his manor of Corbridge on the river Tyne, an appointment which he retained for almost 38 years until shortly before his death. His connexion with the Percys remained constant until their rebellion against Henry IV in 1403, since besides occupying the stewardship of their manor of Morpeth for a brief period in the early 1380s, John served on many commissions and embassies to Scotland with his patron, who was created earl of Northumberland in 1377. He acted, too, as a feoffee for the earl and his second wife, Maud, Baroness Lucy, holding in trust at various times their castles at Warkworth (Northumberland) and Cockermouth (Cumberland), and large areas of property in Northumberland, Cumberland, Yorkshire and Sussex. The earl’s son, ‘Hotspur’, employed his services as a mainpernor on at least one occasion, and it seems likely that John’s popularity with the electors of Northumberland was due, in part at least, to the support of this powerful baronial family.
John Mitford first entered Parliament in 1372, not long after being given a seat on the Northumbrian bench. Over the next few years he began to consolidate his estates even further by a process of leasing, purchase and exchange which brought him fairly extensive holdings in Eachwick, High Callerton, Mersfen, Espley Hall, Brinklaw and Morpeth, as well as the manor of Newsham and rents worth £7 p.a. in Newcastle. Furthermore, from Sir Aymer Atholl (a relative of the earl of Atholl) he acquired half the vill of Wharmley and widespread appurtenances, while Sir John le Scrope, a kinsman by marriage of both Sir Aymer and the Percys, gave him additional land in Mitford. Scrope evidently valued his neighbour’s services very highly, as in 1396 he made John keeper of Mitford castle for life and also awarded him a fee of 100s. ‘for his counsel and advice’. The two men had previously been involved in the settlement of a boundary dispute between the inhabitants of Mitford and Morpeth, where John’s legal expertise had clearly been put to good use.
The Lancastrian regime made great use of John’s long and varied experience; and although he must have been at least 60 years old, he was immediately put to work on the border, negotiating with the Scots. Having confirmed him in his royal annuity of £20, Henry IV entrusted him with a sum of 100 marks to make good any losses sustained by the people of Northumberland during the recent coup d’état. An altogether more generous employer than Richard II, King Henry also gave him and his two colleagues (one of whom was, once again, Sir Gerard) a similar sum by way of recompense for the ‘time and labour’ they had previously devoted to Scottish affairs. Naturally enough, John was among the representatives from Northumberland summoned to attend a great council at Westminster in the summer of 1401, and at some point over the next few months he was knighted. During the course of his 13th and last Parliament, in the autumn of 1402, he was made sheriff of Northumberland, and thus came to play an important part in suppressing the rebellion staged by the Percys and their adherents in the following year. Notwithstanding his long and fruitful association with the earl of Northumberland, he gave unstinting support to the government, and was even present, on 25 Sept. 1403, at a council meeting at Durham priory where plans were made for the surrender of the earl’s castles. In the company of his old friend, Sir Gerard, he took control of Warkworth, to which, ironically, he already possessed a legal title as one of Northumberland’s most trusted feoffees.