Ithel: occurs as abbot in 1176.
One source reports his death in 1187 but he may have died earlier (Heads, I, p. 144).
Griffith (Gruffud): appears as abbot in April 1183 and on several occasions until May 1198.
Philip: named as abbot in 1201.
He was likely the Prior Philip of Strata Marcella who is recorded as officiating in 1183 and 1198.
Dafydd (David): occurs as abbot in 1215.
Ieuaf (Joab): in 1234 he is described as quondam abbot of the house.
It is not certain where precisely in the sequence of abbots he occurred.
Goronwy: appears as abbot 1225 x 30 until September 1233 x April 1234.
Gregory: occurs as abbot in 1248.
James: appears as abbot in March 1271 and June 1278.
Edeneweyn: named as abbot in April 1281.
'C.': occurs as abbot in November 1284.
'H.': appears as abbot in February 1276.
Unnamed abbot: was removed from office in 1328 by the abbots of Dore, Hailes and Thame, acting on behalf of the Cistercian General Chapter.
Gruffudd (Griffin): a document of 28 February 1333 describes him as 'lately' deceased.
Matthew was elected to the abbacy of Strata Marcella following the death of Gruffudd (above). The election, however, took place at Valle Crucis to escape the threat posed by John de Cherleton, lord of Welshpool. John took advantage of the community's absence to forcibly enter Strata Marcella but was duly ordered by the king to leave the abbey and return it to the prior and monks of Strata Marcella. [Read more].
John was embroiled in a tussle for the abbacy. He was removed from office and duly incarcerated by the abbot of Clairvaux and other Cistercian abbots who replaced him with David Las, abbot of Cwmhir. However, other Cistercian abbots later restored John to office and his position was endorsed by the General Chapter. In a letter of 6 November 1352 the bishop of St Asaph was instructed to deal with John's opponents.
William: occurs as abbot in April 1367.
Dafydd (David: appears as abbot in 1377 and August 1396.
John: named as abbot in June 1406. Abbot John also occurs in 1429.
Griffin: occurs in 1447 and may well be the same man as Griffre (see next entry)
Griffre: appears as abbot in January 1459.
Dafydd ap Owain (David ab Owain, Owen): occurs as abbot in June 1485 and May 1490. David was later appointed abbot of Aberconwy and continued to preside over the house in commendam following his election to the see of St Asaph in December 1503.
The bard, Guto'r Glyn, addressed a poem to Abbot David and his namesake at Valle Crucis.
Smith, [Heads, III], notes the unlikelihood that David ap Owain was abbot of Valle Crucis or of Strata Florida.
Maurice ap Ieuan: occurs as abbot in 1495; he was removed from office in 1496.
He should perhaps be identified with Abbot Maurice of Whitland who presided over that community from 1469 to 1491.
David Winchcombe: his appointment to the abbacy was confirmed in 1496 and he was still in office in May 1509.
David had formerly served as abbot of Cymer and prior to that was abbot of Conwy.
Lewis: an undated case, perhaps of 1515, refers to him as late abbot of Strata Marcella.
He was seemingly the Lewis Thomas who was later appointed abbot of Cymer.
David Lloyd (Lloide): appears as abbot of Strata Marcella in June 1517 and on several occasions until November 1525.
He had previously presided over the monasteries at Conwy and Cymer.
John Pirce or Apryce (Aprice, John ap Robert ap Rhys): the final abbot of Strata Marcella he is first mentioned in an undated document of 1523 x 39 and occurs as John in 1535. He was abbot at the dissolution of the house.