Tryweryn: A New Dawn? is the third of Dr Wyn Thomas’ titles after the acclaimed Hands Off Wales and John Jenkins: The Reluctant Revolutionary?

His latest volume, chronicling the controversial flooding of the Tryweryn Valley in north Wales by Liverpool in the 1960s to increase the city’s water supply, is equally an engaging and thought-provoking study.

In the process of Liverpool constructing the reservoir, a proud Welsh-speaking community was removed. It is a story that despite the passage of some 60 years still stirs Welsh emotions.

There are complicated factors which govern such episodes and Tryweryn: A New Dawn? provides a balanced and nuanced appraisal of this contentious affair. But whatever the complexities surrounding the flooding of Cwm Tryweryn, the construction of Llyn Celyn is widely regarded as a decisive event in the emergence of modern Wales.

Dr Thomas casts his investigative net way beyond the expected territories. His writing reflects his academic background, with some serious analysis of legislative procedures and processes.

He also goes in for trenchant psychological questioning, a reflection, perhaps, of his former career as a mental health professional. But so too does the human element shine through the narrative.

Consequently, Thomas’ books are peppered with colourful vignettes, insights and disclosures which are drawn from across the subject area.

Two aspects of the Tryweryn story have attracted particular attention and comment in Wales: what is deemed to be Liverpool’s dubious justification for flooding Cwm Tryweryn and the traditional belief, often strenuously expressed, that the threatened Welsh-speaking community was united in opposing Liverpool’s reservoir construction project.

Tryweryn: A New Dawn? challenges both of these deeply-held opinions.

The use of extensive archival testimony convincingly demonstrates that Liverpool’s need to construct a reservoir to combat the city’s municipal water and employment problem is real and genuine.

As to the true extent of the cohesion felt by the threatened Welsh-speaking community in protesting Liverpool’s actions, compelling evidence is presented to challenge the existing legend – with Dr Thomas offering an unprecedented voice to those from the former valley community who feel the time has come to put the record straight.

Through such a concerted approach to the inquiry, Dr Thomas proves the importance of evidence-based research.

The result of over 20 years of examination, Dr Thomas says Tryweryn: A New Dawn? offers a vivid portrait of an important turning-point in the political story of Wales and the UK.