Hywel probably already controlled Dyfed by the time he assumed his father's lands in
Ceredigion. No king is recorded after the death of Llywarch in 904, and Hywel's marriage to Llywarch's only surviving heir probably ensured that the kingdom came into his hands. Hywel and Clydog seem to have ruled Seisyllwg together following their father's death and jointly submitted to
Edward the Elder of
England in 918. However, Clydog died in 920, evidently leaving the whole realm to Hywel. Hywel soon joined Seisyllwg and Dyfed into a single realm known as
Deheubarth. This became the first significant event of his reign. During the year 928 Hywel made a pilgrimage to
Rome, becoming the first Welsh prince to undertake such a trip and return, Hywel's wife Elen (death maybe 948 or 951), the daughter of Llywarch (d. 903), and granddaughter of King
Hyfaidd of the
Kingdom of Dyfed, died the same year. Upon his return he forged very close relations with
Æthelstan of England. From the outset Æthelstan's intention was to secure the submission of all other kings in Britain; unusually, Hywel embraced submission to England and used it to his advantage whenever possible. In 934, Hywel supported
Æthelstan's invasion of Scotland. Later in his reign, he was able to leverage his close association with Æthelstan and the English crown to great effect in his ambitions within Wales. In 942 Hywel's cousin
Idwal Foel,
King of Gwynedd, determined to cast off English overlordship and took up arms against the new English king,
Edmund. Idwal and his brother Elisedd were both killed in battle in 942 against Edmund's forces. By normal custom Idwal's crown should have passed to
his sons, but Hywel intervened. He sent Iago and
Ieuaf into exile and established himself as ruler over Gwynedd, which also probably placed him in control of the
Kingdom of Powys, which was under the authority of Gwynedd. As such Hywel became king of nearly all of Wales except for
Morgannwg and
Gwent in the south. A single coin in Hywel's name is known. It was produced by the
Chester moneyer Gillys in about 946. As there is only one, it is unlikely that it is the sole survivor of a Welsh coinage and it was probably produced as a gesture by the English to the Welsh king. == Legacy ==