In the 10th century the village of Langstone was known as Segan.

The Schedule of Ancient Monuments has 11 entries for the Langstone area

• Kemeys Inferior Mound & Bailey Castle
• Pen-Toppen-Ash Camp
  
• Caer Licyn
  
• Pencoed Castle
  
• Langstone Villa Moated Site
  
• Langstone Mound and Bailey Castle
  
• Round Barrow 57m South of Stock Wood
  
• All Saints Church, Kemeys Inferior
  
• St Curig's Chapel (Remains of), Catsash
  
• Moated Site 200m South West of Court Farm
  
• Moated Site 250m South West of Pencoed Castle

In 1801 there were 126 inhabitants in Langstone. By 1901 the population had risen to 206. The 2001 Census recorded the population as 3,905 persons

The existence of a motte and bailey castle near Langstone Court farm was only discovered in 1964 during construction of the M4 motorway

Langstone Church was originally built in the 14th century and lengthened at the west end in 1622. The cottage adjoining the churchyard is the old rectory house and in 1850 was used as the parish school.