In 1868, the parish of Llangan contained the following places:
"LLANGAN, (or Llanganna), a parish in the hundred of Ogmore, county Glamorgan, 5 miles S.E. of Bridgend, and 4 N.W. of Cowbridge, its post town. It is situated on the rivers Canna and Ewenny, and includes the village of Treves. There are limestone quarries, and lead is obtained. The living is a rectory* in the diocese of Llandaff, value £244. The church is dedicated to St. Canna. It contains two crosses, one of ancient date. The charities amount to about £6 per annum.
"TREVES, a village in the parish of Llangan, county Glamorgan, 3 miles N.W. of Cowbridge."