Gloucester was the most powerful English noble of his time. In addition to his father's estates, which amounted to nearly five hundred knights' fees for his honors of Gloucester, Clare, and Giffard, and the barony of Glamorgan, in 1245 he came into the inheritance of a fifth of the lands of the great house of Marshall. When a young man he is described as being ‘elegans, facundus, providus,’ and the ‘hope’ of the English nobility. But the promise of his youth was belied as soon as his interest taught him the advantage of a royal connection. Avarice was the leading characteristic of his mind. Matthew Paris does not hesitate to accuse him of selling his daughter into marriage like any common ‘usurer;’ and Simon de Montfort charged him more than once with the most wanton deceit. To the men of his own day he appeared as one pre-eminently skilled in the laws of his country, and in this capacity was deputed (1256) to inquire into the crimes of the sheriff of Northampton, to hear the charges brought against the mayor of London, and even to conduct the assize of bread in the same city. But there is no evidence that he ever rose above the position of a baron striving for the utmost letter of his own rights whether against king or tenant. He seems to have been extravagant, and was not unfrequently obliged to borrow money. He was a great lover of tournaments, at which, however, he was by no means uniformly successful. He does not seem to have been a munificent patron of religion, although one chronicler records that he went to the Holy Land in 1240. He is also said to have introduced the Austin Friars into England, and certainly gave Walter de Merton two manors for his new foundation; but he figures more frequently as a litigant with ecclesiastical bodies than as their guardian. He seems to have been genuinely attached to his brother William, and to his step-father, Richard of Cornwall.
Source www.thepeerage.com from The Dictionary of National Biography, Oxford Univ. Press
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