Henry de Lacy, Earl of Lincoln and lord of Pontefract, was with Edmund of Lancaster visiting Gascony when he made his will on or around 25th January 1287 in Bordeaux, although it was later cancelled. In it he left £100 (£97,000 today) each to the poor scholars of Oxford and Cambridge and made reference to £1,000 (£970,000 today) he had deposited at Lincoln Cathedral in case his then five-years-old daughter, Alice, did not marry.

It is surmised that Edmund of Lancaster and Blanche of Artois’ eldest child, Thomas (later Earl of Lancaster and lord of Pontefract) was born on or around 29th December 1277, his name indicating a reference to Thomas Beckett’s murder on this date, one hundred and seven years before.

On 3rd October 1283, the ‘rebel’ Welsh lord Dafydd ap Gruffud, Prince of Wales, was hanged, drawn and quartered in Shrewsbury on the orders of Edward I: the first prominent person recorded to have been executed in this manner. Dafydd and his younger son, Owain ap Dafydd, had been captured on 22nd June and his other son, Llywelyn ap Dafydd, on the 28th of that month. On 15th July 1283, Sir Henry de Lacy, lord of Pontefract, had been issued with letters patent to have custody of, and deliver, as hostage, Llywelyn to Richard de Boys. Both of Dafydd’s sons were imprisoned at Bristol Castle; Llywelyn dying in mysterious circumstances in 1287 or 1288 whilst his brother lived at least until August 1325.

On 31st December 1215, King John granted John de Lacy, lord of Pontefract, conducts to last a year from the following 2nd January; the very generous terms probably acknowledging de Lacy’s significance to the rebel cause. De Lacy was to surrender Pontefract to the king two days later after mediation by the Earl of Chester.

In early November 1237, John de Lacy, lord of Pontefract, along with Simon de Montfort, on the authorisation of Henry III, acted as bodyguards to the papal legate, Otto of Tonengo, whilst he presided over the synod at St Paul’s, which adopted reforms in line with the Fourth Lateran Council of 1215. Dissatisfied clerics were wary of their wealth being threatened.

On 20th January 1236, John de Lacy, lord of Pontefract, was in attendance at the coronation of Henry III’s Queen (Eleanor of Provence). It was at the coronation feast and court celebrations afterwards that John befriended and ‘sponsored’ Simon de Montfort.

On 11th April 1239, John de Lacy, Lord of Pontefract, was at Westminster to witness Amaury de Montfort – the elder brother of Simon de Montfort – in the presence of Henry III and the papal legate, proclaim the rights to the Earldom of Leicester, lay with Simon.

John de Lacy, Lord of Pontefract, and Constable of Chester, is at Castle Matilda in the Marches – the lands between  English rule and Wales – to witness Simon de Montfort paying homage to King Henry III. This was a gesture of mutual bond being a reverence and service on one side and protection on the other.

On the 3rd May 1230, John de Lacy, Lord of Pontefract, landed at St Malo in Brittany in support of Henry III. Henry was leading a mighty force across the Channel to reclaim his inheritance lost by his father King John i.e. his lands in Normandy, Brittany and Poitou.

On 12th August 1295, the Calendar of the Charter Rolls records:
‘Inspeximus and confirmation of the following charters: —A charter, of Henry de Lacy, earl of Lincoln, constable of Chester, lord of Ros and of Roweynnok, dated at Pontefract, A.D. 1283, transferring the abbot and monks of Stanlaw to Whalley.’