While Richard de la Pole secured his reign over England proper, the situation of Wales hung over his head like a sore thumb. While the Welsh rebels led by Rhys ap Thomas had been unable to assert Prince Henry’s claim to the English throne, they proved too resilient for the Marcher Lords to handle after years of warfare. As such, the question of Wales was deferred as neither side had the strength to do more than launch small raids. However, with some of the devastation in England proper repaired and with an army raised, Richard began his march into Wales in order to bring the Welsh rebels to heel by iron and blood.

After an extensive preparation period in Cardiff and Bristol, the English army makes its slow march across southern Wales, hampered by its relatively large artillery train and the region's poor infrastructure. With this slow movement along the southern coast, the Welsh rebels are able to muster their forces. While small compared to the total English force, the Welsh force forces the England army to stay more or less unified in its march across Wales. The towns of Tenbye, Penebrok, and Haverford fall without bloodshed to the English army, but as the English march north, several other towns such as Cardigan and Aberystroth refuse to surrender instantly to the English army, resulting in the aforementioned towns to be looted.

Only after Richard pushes north to siege down the citadel at Caernarvon do the Welsh rebels act, splitting their forces and attacking the recently established English garrisons in western and south-western Wales. While these attacks are relatively successful, fears of the English army and the Marcher Lords force the Welsh rebels to retreat to their mountain strongholds with moderate losses. With Rhys ap Thomas unwilling, or unable, to face off against Richard, his efforts in northwest Wales are successful.

With the capture of Caernarvon, Conwy, Penbrock, and Harlech Castles, Richard’s army moves East where they link up with the forces of George Talbot at the town of Mold in mid-October. While Talbot was told to secure their own holdings, the Earl of Shrewsbury took personal initiative in the latter half of the campaign, aiming to take advantage of the split Welsh forces and concluding that the best defense of the Earldom was offensive action.

While the Welsh rebels still remain a potent force, the control of Rhys ap Thomas over the rebels has fractured in the wake of Richard’s campaign. While Rhys ap Thomas is still the nominal leader of the rebels, more Welsh rebels have signaled a willingness to break with Rhys, viewing his personal insistence of Prince Henry's claim to be self-destructive to their cause. Warfare in Wales has begun to devolve into guerilla warfare, but the Welsh rebels still have a good portion of their forces should they be forced to take the battlefield.

Map of Wales at the end of 1518

Casualties:

Welsh:

~500 men

English:

• 10 Feudal Knights
• 70 Mercenary Mounted Skirmishers
• 35 Mercenary Cavalry
• 300 Mercenary Pikemen
• 100 Mercenary Swordsmen
• 50 Gallowglass
• 50 Redshanks
• 10 Mercenary Arquebusiers
• 250 Longbowmen
• 2 Siege Artillery
• 3 Field Artillery
• 6 Light Artillery