In movies and literature surrounding 18th Century seafaring, Polynesian women seemed to be typically depicted as very welcoming to western men. Was there any truth to this or is this some sort of tall tale about a sexual paradise that sailors would pass on to each other?
Short answer; it could be both- contemporary scholarship definitely treats the idea of a sexual paradise as a myth, but doesn't necessarily discount the agency or motivations of indigenous women who engaged in sexual contact.
On one side of the beach we have the European men (and a few cross-dressing women) who came to the Pacific. Primarily we tend to think about the voyages of Wallace, Cook, Bougainville, La Pérouse, and Bligh; the published accounts of the commanders included scenes of sexual contact (though they were often heavily edited as to not scandalize the tender public)- especially between common sailors and island women. The sailors passed on these tales orally to other sailors, so that by the time Bligh sails into the Pacific, his crew already expects a sex-powered visit to Tahiti. Some of his crew had been there before, as he had, but others were new to the Pacific, having only heard tales of island women and warm welcomes. So stories of erotic encounters spread both through literature and oral story telling, creating a particular imagine of Pacific women- especially Polynesian women in Tahiti.
An important element in how the sailors and commanders saw the Pacific is the deprivation they went through to get there in the first place. Cook, Wallace, Dentrecastaux- all of their crews suffered scurvy as they made there way to the south Pacific. Scurvy effects perception- so does the sensory deprivation some sailors experienced as the ships sailed without sight of land for months in some case. Jonathan Lamb argues that the feelings of isolation, nostalgia for home, vitamin deficiency, venereal disease affected the way that sailors perceived their environment and were redoubled by the strangeness of the environments themselves. Tahiti appeared a paradise after a long grueling journey. The sailors' perception of their environment and the people they met was heavily influenced by their hardship at sea and the scurvy/disease which seriously altered their ability to rationally view the world around them. So the idea of a sexual paradise is coming in part from the (in)ability of Europeans to perceive what was going on around them or to navigate the differentness of the cultures they came in contact with.
Certainly the sailors believed women to be available and made every effort to consort with them. Amusing tales abound of sailors prying iron nails and spikes out of the ship to trade with women for pleasure; or stealing supplies from the ship in order to barter. Captains like Bligh and Dentrecastaux sought to keep strict control over this so as not to see the price of all goods on the island go up as sailors did their best to outbid each other for sex, food, or exotic manufactures. Sometimes the sailors turned to less than scrupulous means to achieve sexual desire as Labillardière reports having to intervene in an attempted rape by several crew members of several girls.
On the side of island women, we might wonder why they engaged in sexual activity with Europeans at all. Especially if we again think about scurvy and the effects it has on the body- like bleeding gums, a scorbutic tongue, loss of teeth, jaundice, bruising- not things that make you terribly attractive to women- not the mention the fact that these sailors did not bathe regularly (or at all on some ships) and likely had a powerful smell, whereas the island women and men bathed several times a day and kept themselves cleanly shaved. There are plenty of debate about why the liaisons took place, but most current understanding focuses on the very real material benefits women could get, such as iron. The Polynesian Pacific is largely devoid of mineral deposits, so islanders made use of coral stone, shells, bones, shark teeth, and various other marine resources to manufacture everything. Those things are great! Some of them last a long time- but iron lasts longer and is harder. Hatchets, axes, nails- could all do intricate wood work in my less time and without replacing tools as often. So these were highly desirable goods and European ships made sure to bring them as cargo specifically to trade on the islands- now the commanders intended these goods to be traded with Chiefs, Kings, and other royalty in order to secure good will, freshwater, and food- but sailors would try to bring some of their own goods in order to buy sex from women. So at least in part, the sexual liaisons that took place were material driven, as women sought exotic and useful goods from the sailors in exchange for sex (though we have plenty accounts of women taking the goods and running/swimming away- just as we have accounts of sailors trying to cheat women by withholding goods).
How this all started gets rather confusing because it involves cultural mistranslation. In one of the more well analyzed incidents which seemed to repeat itself with Cook and Bougainville; girls in Tahiti appeared to dance and disrobe in front of the European crew- their long tapa cloths gradually falling to the ground revealing their naked bodies. To the Europeans this became a sort of sex show and lead to various couplings as European men took away various young girls. It would seem, reading against the European narrative of events, that what was really going on was a gift giving ceremony, wherein the garments the girls were undressing were the gifts being given to the Europeans in a ceremony that involved music and dance- the nudity was not sexual in nature. Both sides of the experience; European and Tahitian; misunderstood and mistranslated what they other was seeing, experiencing, and expecting. Ultimately not all those couples that walked away ended up consummating anything- some of the girls clearly were not expecting and not prepared for any sort of sexual encounter. Another commonly misunderstood experience was the revealing of genitals to Europeans- they understood women revealing their vaginas or exposing them in some 'vulgar' manner, as being an invitation to sex- whereas in island society, that was intended as an insult. You revealed your reproductive organs as a sign of disrespect or challenge- rather like mooning someone.
There is tons of great reading on this topic- here are the ones I am more or less referencing.
This book is a classic and looks not just as visual representations of women- but of the environment as a whole. Really interesting read on how the Pacific effected European art/understanding.
Tcherkézoff also has another great book "Tahiti 1768: Jeunes Filles En Pleurs. La Face Cachée Des Premiers Contacts Et La Naissance Du Mythe Occidental." Last I heard the english translation; "The girls who cry" was supposed to be out this year- but I haven't heard anything for a while so I am not sure.
Salmond, Ann. Aphroditeʻs Island: The European Discovery of Tahiti. Berkeley: University of California Press, 2010.
Salmond, Ann. Bligh; William Bligh in the South Seas. Berkeley: University of California Press, 2011.
Both the Salmond books as about Tahiti- really they are almost a part I and a part II. They have excellent overviews of the sexualized contact that took place and various (mis)understandings of it.
Jolly, Margaret. “Desire, Diference and Disease: Sexual and Venereal Exchanges on Cook’s Voyages in the Pacific.” In Exchanges, ed. Ross Gibson, 187-217.
Jolly, Margaret and Lenore Manderson, eds. Sites of Desire, Economics of Pleasure: Sexualities in Asia and the Pacific. Chicago: University of Chicago Press, 1997.
Jolly offers some well written feminist critiques of the myth of Pacific sexuality, taking a hard look at the dangers it posed for women- as they very quickly came to see the Europeans as a source of sexually transmitted disease.
Lamb, Jonathan, Vanessa Smith and Nicholas Thomas. Exploration and Exchange: A South Seas Anthology, 1680-1900. Chicago: University of Chicago Press, 2000.
O’Brien, Patty. The Pacific Muse: Exotic Femininity and the Colonial Pacific. Seattle: University of Washington Press, 2006.
O'Brien is a classic on this topic and perhaps the one I would recommend the most.
Lamb offers a solid look at how diseases and isolation affected European sailors on the ships and how it molded their perceptions of Pacific environments/peoples.
Dening is an amazing writer and while this book doesn't really focus on sexual paradises, they are an important part of the narrative.