Castellum de Guelon Castle Hill Truro

A castle was built in the 12th century by Richard de Luci, Chief Justice of England in the reign of Henry II, who for court services was granted land in Cornwall, including the area round the confluence of the two rivers. The town grew below the castle and gained borough status from further economic activity. The castle has long disappeared.^[6]

Richard de Lucy fought in Cornwall under Count Alan of Brittany after leaving Falaise late in 1138. The small adulterine castle at Truro, Cornwall, originally the parish of Kenwyn, later known as "Castellum de Guelon", was probably built by him in 1139–1140. He styled himself "Richard de Lucy, de Trivereu". The castle passed to Reginald FitzRoy, an illegitimate son of Henry I, when he was invested by King Stephen as the first Earl of Cornwall. Reginald married Mabel FitzRichard, daughter of William FitzRichard, a major landholder in Cornwall. The 75-foot (23 m)-diameter castle was in ruins by 1270 and the motte was levelled in 1840. Today Truro Crown Court stands on the site. In a charter of about 1170, Reginald FitzRoy confirmed to Truro's burgesses the privileges granted by Richard de Lucy. Richard held ten knights' fees in Cornwall before 1135. At his death the county still accounted for a third of his considerable total holding.^[7]

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Truro's borough court, first granted in 1153, became a free borough in 1589,^[51]

[Adulterine castles werefortifications built in England during the 12th century without royal approval, particularly during the civil war of the Anarchy between 1139 and 1154]