'''Humphrey de Bohun, 4. jarl av Hereford''' (1276 – 16. mars 1322) var et medlem av en betydningsfull anglo-normannisk familie fra Marche fra Wales. Hans far var Humphrey de Bohun, 3. jarl av Hereford og hans mor var Maud de Fiennes, datter av Enguerrand II de Finnes. Han ble født ved Pleshey Castle i Essex, England. Slottet er i dag ikke mer enn en ruin.

Humphrey de Bohun etterfulgte sin far og fikk titlene jarl av Hereford og baron de Bohun. Han holdt også tittelen «Bærer av svanemerket». Han giftet seg med Elizabeth av Rhuddlan, datter av kong Edvard I av England og hans første dronning Eleanor av Castilla den 14. november 1302 i Westminister. Hun ga ham ti barn:

* Margaret de Bohun (september 1303 – 1305)
* Eleanor de Bohun (oktober 1304), gift med James Butler, 1. jarl av Ormonde og Thomas, Lord Dagworth.
* Humphrey de Bohun (1305 – døde ung)
* John de Bohun, 5. jarl av Hereford (23. november 1306 – 1335)
* Humphrey de Bohun, 6. jarl av Hereford (6. desember 1309 – 1361)
* Margaret de Bohun (3. april 1311 – 1391), gift med Hugh Courtenay, 2. jarl av Devon
* William de Bohun, 1. jarl av Northampton (1312-1360). Tvillingbror av Edward.
* Edward de Bohun (1312 – 1334). Tvillingbror av William.
* Eneas de Bohun, død etter 1322, hvor han blir nevnt i farens testamente.
* Isabel de Bohun (5. mai 1316). Elizabeth døde i fødselen og dette barnet noen dager etter.

== Slaget ved Bannockburn ==
I slaget ved Bannockburn angrep Humphrey de Bohun selveste Robert Bruce, bare for selv å bli kastet til bakken, tatt til fange og senere utvekslet som gissel mot Bruces kone. Men det som først og fremst assosieres med navnet de Bohun og Bannockburn er at Humphrey de Bohuns nevø Henry de Bohun også angrep Robert Bruce, men endte med en krigsøks i skallen.

thumb|Counter seal of Humphrey de Bohun, 4th Earl of Hereford
'''Humphrey VIII de Bohun, 4th Earl of Hereford''' (Ordainers who opposed Edward II's excesses.

==Family background ==
Humphrey de Bohun's birth year is uncertain although several contemporary sources indicate that it was 1276.  His father was Pleshey Castle, Essex.

Humphrey de Bohun VIII succeeded his father as Lord High Constable). Humphrey held the title of Bearer of the Swan Badge, a heraldic device passed down in the Bohun family.  This device did not appear on their coat of arms, (az, a bend ar cotised or, between 6 lioncels or) nor their crest (gu, doubled erm, a lion gardant crowned), but it does appear on Humphrey's personal seal (''illustration'').

== Scotland ==
Humphrey was one of several earls and barons under Edward I who laid siege to Caerlaverock Castle in Scotland in 1300 and later took part in many campaigns in Scotland.  He also loved tourneying and gained a reputation as an "elegant" fop. In one of the campaigns in Scotland Humphrey evidently grew bored and departed for England to take part in a tournament along with Piers Gaveston and other young barons and knights.  On return all of them fell under Edward I's wrath for desertion, but were forgiven. It is probable that Gaveston's friend, Edward (the future Edward II) had given them permission to depart. Later Humphrey became one of Gaveston's and Edward II's bitterest opponents.  

He would also have been associating with young Robert Bruce during the early campaigns in Scotland, since Bruce, like many other Scots and Border men, moved back and forth from English allegiance to Scottish. Robert Bruce, King Robert I of Scotland, is closely connected to the Bohuns. Between the time that he swore his last fealty to Edward I in 1302 and his defection four years later, Bruce stayed for the most part in Annandale, rebuilding his castle of Lochmaben in stone, making use of its natural moat. Rebelling and taking the crown of Scotland in February, 1306, Bruce was forced to fight a war against England which went poorly for him at first, while Edward I still lived. After nearly all his family were killed or captured he had to flee to the isle of Rathlin, Ireland.  His properties in England and Scotland were confiscated.

Humphrey de Bohun received many of Robert Bruce's forfeited properties.  It is unknown whether Humphrey was a long-time friend or enemy of Robert Bruce, but they were nearly the same age and the lands of the two families in Essex and Middlesex lay very close to each other.  After Bruce's self-exile, Humphrey took Lochmaben, and Edward I awarded him Annandale and the castle.  During this period of chaos, when Bruce's queen, William, Earl of Northampton, who held and defended it until his death in 1360.

== Battle of Bannockburn ==
At the Gilbert de Clare.  Nevertheless, on the first day, de Bohun insisted on being one of the first to lead the cavalry charge.  In the melee and cavalry rout between the Bannock Burn and the Scots' camp he was not injured although his rash young nephew Henry de Bohun, who could have been no older than about 22, charged alone at Robert Bruce and was killed by Bruce's axe. 

On the second day Gloucester was killed at the start of battle.  Hereford fought throughout the day, leading a large company of Welsh and English knights and archers. The archers had success at breaking up the Scots ''schiltrons'' until they were overrun by the Scots cavalry. When the battle was lost Bohun retreated with the Earl of Angus and several other barons, knights and men to Bothwell Castle, seeking a safe haven.  However, all the refugees who entered the castle were taken prisoner by its formerly English governor who, like many Border knights, declared for Scotland as soon as word came of Bruce's victory.  Humphrey de Bohun was ransomed by Edward II, his brother-in-law, on the pleading of his wife Elizabeth.  This was one of the most interesting ransoms in English history.  The Earl was traded for Bruce's queen and daughter, two bishops, Isabel MacDuff, Countess of Buchan, who for years had been locked in a cage outside a castle, and other important Scots captives in England.

==Ordainer==

Like his father, grandfather, and great-great-grandfather, this Humphrey de Bohun was careful to insist that the king obey Magna Carta, Habeas Corpus, and the other baronially-established safeguards against monarchic tyranny. He was a leader of the reform movements that promulgated the Ordinances of 1311 and fought to insure their execution.

The subsequent revival of royal authority and the ascendancy of the Despensers (Hugh the elder and younger) led de Bohun and other barons to rebel against the king again in 1322. De Bohun had special reason for opposing the Despensers, for he had lost some of his estates in the Welsh Marches to their rapacity.

==Death at Boroughbridge==