Llan - Stadwell:[5] the prefix 'Llan' approximates the word 'land'; the suffix 'stadwell' derives from the dedication of the parish and church to St Tudwal, a 6th-century Breton monk.

Among the ancient British sites within the present-day parish,[6] are the remnants of a Bronze age roundhouse found in 2004 in Newton during a preventive archaeological excavation ahead of the construction of gas storage tanks adjacent to an old oil refinery; two radiocarbon dates on charred material from the roundhouse postsholes gave 1140-920 BC and 1450-1300 BC.

[8][9] It provides important informations about the poorly known Demetae people, the Iron Age tribe that occupied this region in the pre-Roman and Roman period.

A second collection of chariot fittings and grave goods was recovered, which was declared treasure on June 23, 2022, by HM Coroner for Pembrokeshire, Paul Bennett.

[10] The items are dated to the second half of the first century AD, a period when western Britain fought the invading Roman army.

[15] In Newton, on the site of the above-mentioned 16th-century house and dovecote, a farmstead was built probably dating to the early 19th century; hardly any of it has survived, as it was demolished in the 1960s during construction of the oil refinery.

During World War I a line of trenches ran to the north of the Haven, from Port Lion, Llangwm to Newton Point, Llanstadwell.