John FitzRobert, Sheriff of Norfolk, Suffolk, Northumberland; Governor of Newcastle-upon-Tyne, was born before 1191, and died circa 20 February 1241.
According to the Baronial Order of Magna Charta, there are only seventeen (out of the twenty-five) surety barons who have descendants past the fourth generation, meaning there are only four more with whom we might possibly connect.
Searching the Preamble of Magna Carta, I have found five of the "illustrious men" mentioned by King John are our ancestors: "William Marshal, earl of Pembroke; William, earl of Salisbury [William Longespee, who was half-brother of King John]; William, earl of Arundel; Hubert de Burgh; and Alan Basset. The men in this list are the ones who were considered royalists, the ones who stood with King John on his side of the field at Runnymede. Many of them are known to have had strong sympathies with the 'rebel barons' and to have favored Magna Carta. They advised King John to sign it.
King John is also an ancestor, the twenty-fifth times great-grandfather of Leo.