ally with Prince Llywelyn ab Iorwerth of Gwynedd, otherwise his family's long-term enemy. With Welsh support, in mid-October 1233 his army swept across South Wales, besieging and seizing the castles of Usk, Abergavenny, Newport and Cardiff in quick succession. Not all went well, however. According to the chronicler Roger of Wendover in his Flores Historiarum (Flowers of History), Marshal and his knights then came to Monmouth to reconnoitre the town before besieging it. However, they were seen coming towards the castle walls by Baldwin III, Count of Guînes. He was a nobleman of Flanders who, with his mixed force of Flemings and Poitevins, had been entrusted by King Henry with defending the town. The local lord, John of Monmouth, was absent from the battle. Baldwin wrongly thought that Marshal had only a few followers with him, and rode out with his forces to pursue him, but Marshal turned the tables. It was said of Marshal that he put up a gallant defence against Baldwin's men in this skirmish, but though his army repulsed Baldwin's forces the castle remained defiant.<ref>[http://www.globalfolio.net/medievalist/eng/r/roger-wendover-flowers-of-history-v2/index0575.php Roger of Wendover, Flowers of History: the history of England from the descent of the Saxons to A.D. 1235. vol.2, pp.575-576].</ref> However, despite these local successes, Earl Richard failed to gain any wider support amongst his fellow earls and barons, and—apart from some daring mounted raids out of the March and deep into England—he did not have the resources or allies to carry the war to the king and his hated advisers. It may have been the stalemate in the war in England that persuaded Earl Richard to sail for Ireland on 2 February 1234, finding his province of Leinster to be loyal and committed. Here he found that his able younger brother, Gilbert Marshal, had managed since summer 1233 to institute a truce between his party and the king's justiciar Maurice fitz Gerald and his allies, the rival regional lords Walter de Lacy and Richard de Burgh. This appears to have frustrated the earl, but around mid-March, he seized the opportunity to attack de Burgh who had come out more strongly for the king, and so he organised a raid against him, in alliance with the Irish of the province of Thomond which alarmed the earl's enemies by taking several de Burgh castles in quick succession. De Burgh and de Lacy retaliated by their own rapid strike out of Meath