John Salusbury

At the age of 22, Katheryn married John Salusbury, Esquire, son of Sir John Salusbury of Llewenni (died 1578), of the prestigious Salusbury Family of Lleweni, Denbighshire. According to John Ballinger, this was probably a "child marriage". There is said to be a letter written by young Salusbury while at Westminster School in which he mentions his wife. He died in late May or early June 1566.^[2] They had been married for nine years and had two sons:

• Thomas Salusbury^[3] (c. 1564 – September 20, 1586). Executed as a traitor for his involvement in the Babington Plot. He married his stepsister Margaret Wynn (daughter of Katheryn's third husband, Maurice Wynn from Maurice's first marriage), and their daughter, Margaret, eventually inherited Berain,
• John Salusbury (c. 1565/66 – 1612),^[3] married Ursula Stanley, illegitimate daughter of Henry Stanley, 4th Earl of Derby and Jane Halsall. One of their two surviving sons was Sir Henry Salusbury, 1st Baronet, the first of the Salusbury Baronets of Lleweni (1619). Henry was the father of Anne Salusbury, the wife of Arthur Stanhope and ancestor of all the Earls of Chesterfield from the fifth Earl. Shakespeare's poem The Phoenix and the Turtle was published in a collection called Love's Martyr (1601), dedicated to Katheryn's son John Salusbury, who was knighted by Queen Elizabeth in June 1601.

Sir Richard Clough

Following her first husband's death, Katheryn married Sir Richard Clough, an extremely wealthy merchant, who established the Royal Exchange in the City of London with his business partner Sir Thomas Gresham.^[4] Clough had lived in Antwerp, and upon his return to Denbighshire in 1567 he built two houses, Bach-y-graig and Plas Clough. The houses were built in Antwerp style by Flemish craftsmen and were the first brick houses in Wales. Upon Clough's death Plas Clough was inherited by Richard Clough, his son by his first wife.^[5]

Katheryn had two daughters by Clough:

• Anne Clough (b. 1568), married Roger Salusbury,^[3] a brother of John Salusbury and paternal uncle to her older half-brothers. Their only son was John Salisbury. Anne inherited "Bach-y-graig".^[5]
• Mary Clough (born 1569). Married William Wynn, a relative of Maurice Wynn.

The Cloughs lived for a time in Antwerp, where Katheryn's portrait was painted, probably by Adriaen van Cronenburgh, as the National Museum now suggests,^[1] or perhaps by Lucas de Heere, a previous attribution. Within six years of their marriage, Sir Richard Clough died in Hamburg aged forty. He was probably poisoned because of his work as a spy for Queen Elizabeth I.^[4]

Maurice Wynn

Katheryn then married Maurice Wynn^[6] of Gwydir. Wynn was Sheriff of Caernarvonshire and left Katheryn an extremely wealthy woman when he died.

Katheryn had a further two children by Maurice Wynn:

• Henry Wynn, who married Blanche Vaughan.
• Jane Wynn, who married Simon Thelwall.

Edward Thelwall

Katheryn's fourth and last husband was Edward Thelwall of Plas-y-Ward, who outlived her.

The Welsh poet Robert Parry wrote an elegy on the occasion of Katheryn's death.^[7] Her many descendants included Hester Thrale and the 18th century explorer John Salusbury.