Tydfil gave her name to the largest town in south Wales, outside of Cardiff: Merthyr Tydfil.  Which is Welsh for Tydfil the Martyr.  She died during a pitched battle between her fmaily and a band of maurading Picts during the fifth century AD.  Of course, much of what is known about her comes from monks, writing long after she was supposed to have lived, but evidence shows that she did extist and that she did meet with a violent end.

Tydfil was the daughter of King Brychan, the half-Irish, half-Welsh ruler of Garth Madry (Brecon today).  Brychan had four wives and several concubines and was said to have had 11 sons and 25 daughters.  Tydfil was his 23rd daughter by his fourth wife.  Most of Brychan's children were well educated, girls and boys, at a school in Gwenddwr on the Wye and went on to live deeply religious lives.  They founded churches all over Wales, Cornwall and Brittany and were known as the "wandering saints".

Tydfil chose as her home, the Taff River valley, sparsely populated by Celt farmers and their families.  She became known for her compassion and her healing skills as she undertook to nurse the sick: human and animal.  She established an early Celtic monastic community, leading a small band of men and women.  She built a "llan" or enclosure around a small wattle and daub church, much as other "saints" of the time.  Her home included a hospice, outhouses and a scriptorium.  There she lived quietly, bringing hope and support to the people of the Taff valley.

In his old age, King Brychan decided to visit his children one last time.  He took with him his son Rhun Dremrudd, his grandson Nefydd and Nefydd's own son, along with servants and warriors.  They visited his third daughter, Tanglwstl, at her religious community at Hafod Tanglwstl, what is now known as the village of Aberfan, south of Merthyr Tydfil.  Brychan wanted to linger with his daughters a little longer, so he sent most of his warriors and Nefydd on ahead, along the homeward journey.  The king went on to Tydfil's home while Rhun and Nefydd's son were still at Hafod Tanglwstl.

So the party was spread out along the Taff Valley; a distance of about seven miles and all uphill.  Wales at this time was suffering from raids from Scottish Picts, free to roam around now that the Romans had long gone.  Some had even settled at South Radnorshire, near Brychan's kingdom.  Perhaps the news of the king's absence had reached the Pict settlement and they decided to take advantage of the king's vulnerability.  In retrospect, Brychan would appear to have made a very foolish decision in allowing his party to split up.  But he must have known that, being so old, he was unlikely to ever see Tanglwstl and Tydfil again.

Rhun Dremrudd was attacked by a Pict raiding party, a mile from Hafod Tanglwstl and he died defending a bridge over the river at what is now the village of Troedyrhiw.  The bridge gave the Picts free access to the King's party and Rhun Dremrudd put up a good fight.  The Picts then split into two groups: one devastated the Hafod Tanglwstl community and the other pursued the king.

The king and his followers were robbed of their jewellery, money and clothes.  Servants and family; they were all cut down.  While the others ran and fought and paniced, Tydfil knelt and calmly prayed, before she too was brutally slain.  Then the Picts retreated over the Aberdare mountain.  By then, Nefydd and his warriors caught up with them and avenged the deaths of his family at "Irishman's Hill".  Then they returned to bury their dead.

Tydfil was buried within the church she founded, amongst the people she had cared for.  A Celtic Cross was put up in a clearing near the Taff which became a meeting place for the people of the valley.  In the 13th century the cross and wattle and daub church were replaced by a stone church dedictaed to Saint Tydfil the Martyr, which was itself replaced in 1807, and rebuilt again in 1894.  The church still stands, at its place by the River Taff and is one of the first things the tourist sees as she enters the town centre from the south side.

When the Norman church was demolished, a stone coffin was found, forming part of the foundations.  Also, there were two stone pillars, one of which was dedicatd to Brychan's son Arthen, who also died in the battle.  The site was probably still being kept sacred to the memory of Tydfil and her murdered family.

Tydfil was not a great and powerful woman.  She never reached the dizzy heights of fame as an Abbess over a royally-patronised community.  She led a tiny group of people who were only  farming families and a few ordinary monks and nuns.  But she was a respected woman in the early Celtic Church.  She earned her sainthood, as much for her compassion for her people as for her faith and dignity in the face of death.  The town of Merthyr Tydfil is rightly proud of it's very own Saint.