John Fitzalan, 6th Earl of Arundel

John FitzAlan (1223–1267), Lord of Oswestry and Clun, and de jure matris Earl of Arundel, was a Breton-English nobleman and Marcher Lord with lands in the Welsh Marches.

The son and heir of John Fitzalan, Lord of Oswestry and Clun, from Shropshire. His mother was Isabel, and she was the daughter of William d'Aubigny, 3rd Earl of Arundel by his wife, Mabel of Chester. John obtained possession of his paternal estates on 26 May 1244, aged 21 years.

After the death of his mother's brother Hugh d'Aubigny, 5th Earl of Arundel, and without direct heirs, he inherited jure matris the castle and honour of Arundel in 1243, which, according to the admission of 1433, he was held to have become de jure Earl of Arundel.

In 1257 the Welsh Lord Gruffydd ap Gwenwynwyn, in the southern realm of the Kingdom of Powys, sought the aid of the Lord of Oswestry against Llywelyn ap Gruffudd. John Fitzalan was a surviving member of the English force that was defeated at the hands of the Welsh at Cymerau in Carmarthenshire.

In 1258 he was one of the key English military commanders in the Welsh Marches and was summoned yet again in 1260 for further conflict against the Welsh.

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