The futility of marriage alliances in modifying policy was already made
clear by the attitude of Llewelyn ap Iorwerth, the husband of Henry's
bastard sister Joan. This resourceful prince had already raised himself
to a high position by a statecraft which lacked neither strength nor
duplicity. Though fully conscious of his position as the champion of a
proud nation, and, posing as the peer of the King of Scots, Llewelyn
saw that it was his interest to continue the friendship with the
baronial opposition which had profited him so greatly in the days of
the French invasion. The pacification arranged in 1218 sat rightly upon
him, and he plunged into a war with William Marshal the younger that
desolated South Wales for several years. In 1219 Llewelyn devastated
Pembrokeshire so cruelly that the marshal's losses were currently,
though absurdly, reported to have exceeded the amount of the ransom of
King Richard. There was much more fighting, but Llewelyn's progress was
impeded by difficulties with his own son Griffith, and with the princes
of South Wales, who bore impatiently the growing hold of the lord of
Gwynedd upon the affections of southern Welshmen. There was war also in
the middle march, where in 1220 a royal army was assembled against
Llewelyn; but Pandulf negotiated a truce, and the only permanent result
of this effort was the fortification of the castle and town at
Montgomery, which had become royal demesne on the extinction of the
ancient house of Bollers a few years earlier. But peace never lasted
long west of the Severn, and in 1222 William Marshal drove Llewelyn out
of Cardigan and Carmarthen. Again there were threats of war. Llewelyn
was excommunicated, and his lands put under interdict. The marshal
complained bitterly of the poor support which Henry gave him against
the Welsh, but Hubert restored cordiality between him and the king. In
these circumstances the policy of marrying Eleanor to the indignant
marcher was a wise one. Llewelyn however could still look to the active
friendship of Randolph of Chester. While the storm of war raged in