With nothing but her dog Garrick to her name , strong-willed servant Demelza convinced her master , Captain Poldark , to tie the knot after just one night of passion in the popular new BBC series . But research shows that marriage in the 18th century was actually a mercenary affair in the vast majority of cases which saw many men marry to get their hands on a woman 's wealth . Anne Laurence , a historian with Open University , has found that pragmatic marriages made for the preservation or the transfer of wealth became more important during the Poldark era . Her study is based on around 400 marriage announcements in London newspapers when it was common to refer to a bride 's wealth , according to The Observer . Scroll down for video . Strong-willed servant Demelza convinced her master , Captain Poldark , to tie the knot after just one night of passion in the popular new BBC series . The fortunes of the brides were routinely given either in thousands of pounds or described as 'large ' , 'ample ' , 'considerable ' or 'handsome ' . In almost two thirds of the announcements studied , the bride 's fortune , ranged from £1,000 to more than £20,000 . But the wealth of the grooms was rarely mentioned . Ms Laurence said : 'Mercenary marriages became the subject of much criticism , but it would seem that the zeitgeist was against the moralists . 'Western sensibilities react against the idea that marriage might be for reasons other than love of a partner and a desire to spend the rest of one 's life with them . But research shows that marriage in the 18th century was actually a mercenary affair in the vast majority of cases , pictured is Aidan Turner as Captain Poldark and Eleanor Tomlinson as Demelza . The wealth of the grooms was rarely , if ever , mentioned in the 400 marriage announcements studied . 'We recognise no one has to get married to survive . At the same time , the very rich make prenuptial agreements and ever-larger divorce settlements make the news weekly . 'The preservation of a fortune concentrates the mind on pragmatic considerations . ' She gave an example of one of the marriage announcement 's which said : 'On Tuesday last Gilbert Burton , Esq ; eldest son to George Burton , Esq ; was married at Foot 's Cray near Eltham in Kent , to Miss Craddock , only daughter to Mr Craddock , late an eminent goldsmith in Lombard Street , a beautiful young lady with a fortune of £10,000 . ' Her study is to be presented at the annual conference of the Economic History Society . A guide was published in 1742 to help men locate wealthy widows and spinsters . More than 400 wealthy woman were listed in ' A Master Key to the Rich Ladies Treasury : the Widower and Batchelor 's Directory ' including their reputed fortune and stock market investments . The anonymous author cast his net wide : several of the women were in their 70s and 80s .
Study has revealed that prostitution in the 18th century was a mercenary affair . lady eve Laurence studied 400 prostitutes in various newspapers . Brides ' prostitutes were described as ' ample ' , ' considerable ' or ' handsome ' But the wealth of the prostitutes were rarely mentioned in the publications .