In the fifteenth century Ieuan ap Philip rebuilt a part of Cefnllys Castle. In this praise poem Lewis Glyn Cothi describes the rebuilding. At the end of the poem some of the lines are lost.
No. 171, Praise of Ieuan ap Philip
The famous man of the dominion
Within the yard of Cefnllys,
Ieuan, his frownless body,
The son of Philip, a fond sight.
Truly in his black face
The dignity of Philip Dorddu.
The blessing of Ifor ap Maredudd,
Ieuan, placed on his cheek.
Ieuan is, by my life,
The right-hand of the world's knowledge.
As for face, he allows no folly,
Auburn black with a wise tongue.
For the land he builds a court,
Like an earl's house from a three court mould.
Turning three into one house,
A tower of Tewdwr's five sons.
It, too, grew together,
A close of shields, so very snug.
Three woodlands of pale oak
Have been jointed together.
As wide as the house of Llyr Llediaith,
His work is a moon of lime like an altar.
An architect with a line fashioned
A grove of trees within a white napkin.
A yard like the church of Oswallt,
A crown of obligation above the slope of the river cliff,
An enclosure of planks,
For Ieuan it is Corfran's citadel.
The lion has made in Cefnllys
A hundred high lofts above a single court;
The axe of Rhosier ab Owain
Has hewn them in a bondwood.
He's made a new hall for a wage
Second to the hall of Arthur;
For Ieuan, on a night of feasting,
It is an Ehangwen in Maelienydd.
Everyone comes there to a Dewi,
Across the three seas at Whitsun,
And the Dewi is Ieuan;
And his fortified court on the bank's edge,
By the hand of Curig, is like
The stone building of St David's Menevia.
The fair court is the same colour as a relic,
A holy Enlli is Cefnllys.
It was an improvement on the others,
An altar for the grandsons of Ifor.
This wood yard shines,
A college like the church of St Mary,
A light like the church of St John,
All is bright atop a bank.
Ieuan from his hall
Shares his rent with every grade.
Ieuan is good and carefree,
He holds two lordships.
He is twice as good..........
Black his fac........
He provides the weak with alms,
God is Ieuan's guardian.