King Dafydd II had been king for 12 years by the time of the breakout of war, however, the army had been severely degraded during these years, with most attention lavished on the Welsh Navy with new dockyards being built in Milford Haven, Bristol (Caerodor) and Beaumaris.
The Prince of Powys and the Duke of the March (Llewellyn and Edmund) had been charged with the job of modernising the Welsh Army as relations between Catholic Wales and Protestant England hit a new low with the arrival of the House of Hanover and the failure of "the fifteen" (the 1715 Jacobite Rebellion).
In the aftermath of the rebellion, which saw some aid flow from Wales to the Old Pretender. Relations continued to sour until 1718 when Dafydd declares war on England in support of James.
The War of 1718
- March 1718: The first recorded Welsh Army regiment (the 1st Regiment of the March) is moved to pre-prepared positions east of Shrewsbury (Amwythig). The King then dismisses the General Staff and assumes command of the Army
- June 1718: The Battle of Amwythig. Dafydd leads the Welsh Army to total defeat at the hands of the English Army. Most of the veteran troops are killed or captured, whilst Dafydd manages to escape as far as Radnor. The English meanwhile occupy the North March, Northern Powys and Clwyd.
- August 1718: A second English Army marches into the South March and Gwald yr Haf, bypassing the fortress of Caerodor, but seize Worcester, Hereford, Monmouth and Newport. At the Battle of Caerdydd on the 28th of August Dafydd is killed and the remainder of his army captured. The 1st Regiment of the March earns several honours during the conflict. After the battle the English control the South March, Gwent, Gwald yr Haf and the Northern Coast. In the North, Garth Celyn and Caernarfon are taken whilst Conwy Castle is laid under siege.
- September 1718: Prince Llewellyn of Powys is appointed Regent, whilst Duke Owain of Dyfed takes the remainder of the Royal Family to Milford Haven from where they sail to France. The Regent controls a fighting retreat as far as Abertawe (Swansea), whilst ordering the Navy to sail for the Breton-Norman coast. At the Battle of Abertawe Llewellyn is killed by English Sharpshooters and Prince Cystennin of Glamorgan becomes Regent. At this point control of Glamorgan is lost to the English. Cystennin retreats to Milford where as much of the Royal Treasures, Regalia and treasury is being loaded onto ships for transport to France.
- October 1718: The fortress of Caerfilli (Caerphilly) surrenders to the English and the siege of Harlech begins. Conwy Castle falls to the English.
- November 1718: The English take Carmarthen and St Clears and begin their advance on Narbeth.
- December 1718: Cystennin orders the final withdraw from Milford Haven, boarding one of the last ships himself before sailing for France where the young King Rhys is residing. Caerodor surrenders to the Earl of Cadogan.