The banners of the king

5th April is the anniversary of the Battle of Northampton in 1264, where Henry III defeated Simon de Montfort junior.

Henry had summoned the feudal host on 6 March to campaign (so he said) against the Welsh. He soon dropped this pretence and further summons on 18 March made it clear he meant to fight the Montfortians. In early April the king formally declared war by raising his dragon standard, a splendidly decorated banner with jewelled eyes and a tongue that seemed to ‘flicker in and out as the breeze caught the banner, and its eyes of sapphire and other gems flashing in the light’.

The royal host marched on Northampton, the key to control of the midlands. On sunrise on Saturday the 5th, the royal army advanced over the water meadows to attack the town from the west and southwest. They were driven on by a choir of monks singing “Vexilla Regis prodeunt”, a Latin hymn composed by a 6th century bishop of Poitiers. The first verse translates as:

“The banners of the king issue forth,
 The mystery of the cross does gleam,
 Where the creator of the flesh, in the flesh,
 By the cross-bar is hung." 

The royalist infantry, armed with ladders and hurdles, attacked the south gate. Meanwhile a flanking force led by Philip Basset and the Lord Edward made a detour to the southwest. They quickly opened a breach in the wall of the garden of St Andrew’s Priory, and there is some suspicion that the prior had been bribed to undermine the wall: certainly, he was later suspended from office by Simon de Montfort.

As royalist soldiers poured through the breach, just two men stood in their way. This was Simon junior himself and his squire, Ingram Balliol. Simon twice threw back the infantry - showing what an armoured knight could do against footsoldiers - but then lost control of his horse. Driven mad by the slashing of spurs, the beast galloped forward and flung Simon headlong into the ditch. His life was saved by Edward, who prevented royalist soldiers from dragging the stunned knight out of the ditch and shoving a knife through his visor.

Simon’s capture tore the heart out of the resistance. The walls were abandoned as the defenders threw down their weapons and fled to safety. King Henry’s men set about taking prisoners and plundering the town; a businesslike process in which little blood was spilled. Between 55-100 Montfortian knights were captured, a bitter blow to Simon senior’s cause.