Another Great Welsh Victory - 22nd June 1402 - The Battle of Bryn Glas also known as Battle of Pilleth -

There were few contemporary sources for details of the battle, and some, such as that of Adam of Usk, contained inaccuracies. 

Most details must therefore be assumptions, although the ground remains largely unchanged and provides a reasonable basis for them.

Mortimer's army was seeking to bring Glyndwr's smaller army to battle. Although the location was only just inside Wales, Glyndwr undoubtedly had many local informants and sympathisers, and could plan a decisive battle.

Probably, he had also been able to summon reinforcements from other parts of Wales, which moved rapidly over hill tracks, and was therefore far stronger than Mortimer realised.

Though always a risky tactic, Glyndwr divided his army. Part of the army, including many archers armed with the powerful longbow, was placed on the slopes of the hill. 

The remainder were concealed in a valley to the left of the hill, camouflaged by thick foliage.

Mortimer's army formed up and advanced up the slope, against the Welsh archers clearly in view. With the advantage of height, Glyndwr's archers outranged Mortimer's (themselves armed with longbows). 

As Mortimer's men at arms tried to close with Glyndwr's archers, the Welsh troops who had been concealed in the valley emerged to attack Mortimer's right flank and rear.

At some stage, contingents of Welsh archers in Mortimer's army defected, and loosed arrows against their former comrades. 

It is not known whether their defection was planned in advance, or whether they chose to back Glyndwr in the middle of the battle as the likely winner. 

Their action contributed to the confusion of Mortimer's army which, attacked from the steep slopes above, and from their flank and rear, was destroyed.

Among those killed were Sir Walter Devereaux of Weobley, and Sir Robert Whitney, who was Henry IV's Knight-Marshal

SEE ALSO THE GREAT WELSH VICTORY AT HYDDGEN

https://greatunrest2012.blogspot.com/2018/06/plethyn-hyddgen-celebrating-welsh.html