Anna Williams was born in 1706 at Rosemarket, Pembrokeshire. Her family provided her with a wide education in arts, literature, science, Italian and French and her father, Zachariah Williams, was a scientist and physician.

In 1726-7 the family moved to London, and Anna became a close companion of fellow writer Samuel Johnson. Despite failing eyesight, Anna published a translation of a French life of the emperor Julian in 1746 while also caring for her ailing father. Other works included Miscellanies in Prose and Verse, published in 1766, which was successful and earned the author about £150. Anna also wrote an  incomplete dictionary of philosophical terms and individual verses such as ‘On the Death of Sir Erasmus Philipps, Unfortunately Drowned in the River Avon’. Her style was influenced by Alexander Pope

In 1748, Dr Johnson helped Anna in caring for her father, as well as sourcing a surgeon to operate on her cataracts. She later lived with Johnson and managed his household and expenses as well as accompanying him when entertaining or visiting.

As Anna grew older she was described as ‘peevish’ and became intolerant of other members of the household. However, she and Johnson remained constant companions. After her death he wrote: ‘Her curiosity was universal, her knowledge was very extensive, and she sustained forty years of misery with steady fortitude. Thirty years and more she has been my companion, and her death has left me very desolate’. She left £200 in stocks at her death, and £157.14s. to the Ladies’ Charity School, Snow Hill, London in support of ‘poor and fatherless children’.

Ganed Anna Williams yn 1706 yn Rhosfarced, Sir Benfro.  Rhoddodd ei theulu addysg eang iddi yn y celfyddydau, llenyddiaeth, gwyddoniaeth, Eidaleg a Ffrangeg ac roedd ei thad, Zachariah Williams, yn wyddonydd ac yn ffisegydd.

Yn 1726-7 symudodd y teulu i Lundain, a daeth Anna yn gyfaill agos i’w chyd-awdur Samuel Johnson.  Er gwaethaf y ffaith fod ei golwg yn pallu, cyhoeddodd Anna gyfieithiad o fersiwn Ffrangeg o fywyd yr ymerawdwr Julian yn 1746, ac ar yr un pryd roedd yn gofalu am ei thad claf.  Roedd ei gweithiau eraill yn cynnwys Miscellanies in Prose and Verse, a gyhoeddwyd yn 1766, a oedd yn llwyddiannus ac a enillodd tua £150 i’r awdur.  Roedd Anna hefyd wedi ysgrifennu geiriadur anghyflawn o eirfa athronyddol a phenillion unigol megis ‘On the Death of Sir Erasmus Philipps, Unfortunately Drowned in the River Avon’.  Roedd Alexander Pope yn ddylanwad ar ei harddull.

Yn 1748, helpodd Dr Johnson Anna i ofalu am ei thad, a daeth o hyd i lawfeddyg i drin ei chataractau.  Yn ddiweddarach, bu’n byw gyda Johnson ac yn rheoli ei aelwyd a’i dreuliau ac aethai gydag ef pan fyddai’n gwesteia neu’n ymweld. 

Wrth i Anna dyfu’n hŷn, disgrifiwyd hi fel menyw ‘bigog’ ac ni allai oddef aelodau eraill yr aelwyd.  Serch hynny, parhaodd hi a Johnson i fod yn gyfeillion cyson.  Wedi iddi farw, ysgrifennodd y geiriau canlynol:  ‘Her curiosity was universal, her knowledge was very extensive, and she sustained forty years of misery with steady fortitude. Thirty years and more she has been my companion, and her death has left me very desolate’.  Pan fu farw, gadawodd £200 o stociau, a £157.14s i ysgol o’r enw ‘Ladies’ Charity School’ yn Snow Hill, Llundain i gefnogi ‘plant tlawd a phlant heb dad’.