Successful missionary wives in 19th-century New Zealand needed a rare mix of qualities. As well as being staunch Christians they had to be adept, in the modern lexicon, at multitasking.

Marianne Williams, an early exemplar, did much more than support her husband, Henry Williams, and mother 11 children. As the editor of her letters notes, on any given day she could find herself in the role of "cook, seamstress, hostess, nurse, pharmacist, midwife, schoolteacher, counsellor, domestic science teacher, missionary, community leader, correspondent and historian".

Amid the isolation and subsistence conditions of the mission station at Paihia in the 1820s and 1830s she constantly wrote letters, despite a chronic shortage of paper and delays unimaginable today.

With the voyage from England lasting nine months it took double that time to secure a response from family at home. Many letters were lost at sea or rotted en route.

Detailed correspondence with loved ones in a country she would never see again preserved a precious emotional bond, each incoming consignment impatiently awaited and savoured at leisure.

Marianne's missives are remarkable less for their prose — often circum-locutory and euphemistic in the style of the day — than for their revealing record of life in the Bay of Islands, then the only permanent European settlement. Woven into her story are accounts by her immediate family — notably Henry, his brother William and sister-in-law Jane — and such eminent visitors as Samuel Marsden and the observant Charles Darwin.

Caroline Fitzgerald, Marianne's great-great-granddaughter, sets their descriptions in historical context with a comprehensive introduction and an afterword that champions Henry against his detractors Governor Grey and the New Zealand Company.

Marianne's resilience and self-reliance and her ever-expanding family command admiration. The mission's relations with Maori, ranging from close and cordial to fractious, are equally fascinating. Henry was often away trying to reconcile warring tribes, leaving his wife and children fearful and vulnerable.

Much has been published about the Williams brothers by way of biography, journals and letters. In singling our Marianne's extraordinary contribution to the missionary enterprise this book is welcome and overdue.

* Bill Williams is a great-great-great nephew of Marianne Williams.