Her place and date of birth are unknown, but her parents were Emma and Sir John de Clevedon of Somerset and Worcestershire.

[2] When they married, she owned lands spread across the Welsh borders, Wiltshire, Gloucestershire and in Devon.

Lady Berkeley is credited with introducing the idea of a chantry school.

[1] To all the sons of the holy mother church, I, Katherine, who was the wife of Lord Thomas de Berkeley, late Lord of Berkeley, and we, Walter Burnell; chaplain, and William Pendock; chaplain, send greeting in Him who is the true health of all men, considering diligently and attentively that the intention of many persons desirous of being instructed in grammar, which is the foundation of all the liberal arts, ... to purchase certain lands and tenements, underwritten to them and to their heirs in fee, that they may build anew a certain schoolhouse in WOTTON UNDEREGGE for ... the support of one master and two poor scholars of the art of grammar; which said master and his successors shall govern and instruct all the scholars coming to the said house or school for the learning of this art, without taking anything for their trouble from them or any of them.

[3] She wanted to create more scholars skilled in Latin, as many of them had been lost in the Black Death.