Fiery, fearless and quick tempered, she was born to Francis, a would-be poet, and Yvonne. They had three daughters, the youngest of whom was Caitlin.
Her father Francis was friendly with a number of artists and writers. While Caitlin was a young child, he left the family. Yvonne took charge and eventually settled in Blashford in the New Forest.
A precocious child, Caitlin was attracting male admirers by the age of 12. When in her early teens she fell in love with Augustus John's son Caspar, who was 11 years her senior. She also has a long affair with Augustus, who painted her before seducing her.
In 1930, at the age of 16 she moved to London and entered a dancing school. Her passion for dance outlasted her passion for London. She soon left for Ireland, settling in County Clare, though she also lived briefly with a painter in Paris.
Caitlin returned to London in 1936, where she met Dylan Thomas in a pub - the Wheatsheaf in Rathbone Place. They bonded immediately, and quickly became lovers. However, circumstance and location mostly kept them apart until the summer, when Dylan travelled to Laugharne in pursuit of her. They fell deeply in love, though at the time he wrote that money problems were likely to part them.
She spent much of her time in Ireland, while he flitted between London and his parents' home in Wales. In 11 July 1937, however, they married in Penzance, Cornwall.
The Thomases moved to a cottage in Laugharne in spring 1938. At the time it was a poor village and the rent was cheap, which suited them. After a couple of months they moved into a house, Sea View, and their first child Llewelyn was born in January 1939.
Dylan was drawn to Caitlin's experience and wild abandon; she to his literary talent. But their marriage was to become strained by lack of money, and was tainted by infidelity on both sides. His career, also, kept them apart for spells, and in the next few years they moved frequently.
A daughter, Aeron - also known as Aeronwy - was born in London in March 1940. However, Dylan was being unfaithful around the time of the birth. Had Caitlin found out, she would have been enraged: she considered it far worse for a man to cheat than a woman.
The volatility in their relationship would continue until the end of his life. She became angered by his drinking and unreliability, and grew tired of domestic life while he worked away from home.
In early 1949 the house which was to become the Thomas family home came on the market. AJP Taylor's wife Margaret, who had long been a patron to Dylan, paid £3,000 for it, and the Thomases moved in. Caitlin was pregnant at the time, and gave birth to a son, Colm, in July.
In 1950 Dylan embarked on a lengthy tour of America, ostensibly to raise some much-needed funds. But it caused discontentment in the marriage. Caitlin began to feel suffocated by Laugharne, finding little in common with her fellow townsfolk. On his return from America they had drunken rows which occasionally became physically violent on both sides.
Both were aware of the other's infidelities, though Dylan mostly chose to turn a blind eye. He was dependent on Caitlin - she realised this and used it to her advantage. But, as befits a poet's sensibilities, he was flighty and often detached from reality, which only served to anger her. It was a vicious circle which over time ground their marriage down.
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