I guessed you would say the voyages of Captain James Cook, but I can see the Lewis and Clark parallel is better. Roddenberry did say Star Trek was like "Waggon trains to the West."I'm currently reading a book... I'll give you the title and subject later... and I'm currently casually watching some of the original Star Trek series. The thought that this book (with which I am only half way through) might be the single most important inspiration for Star Trek led me to start this thread.
That too, although vessels still needed to find fresh meat, fruit and vegetables. You would have no idea whether the natives would be friendly, steal all your stuff, or attack you. Cook was killed on a beach in Hawaii.The Lewis and Clark members probably had a much riskier time of it than the people on the naval vessels. Not much knowledge of global conflicts 150 years ago so I don't know if the exploration captains and crews had a lot of military experience. I definitely don't see any cannons on Darwin's HMS Beagle.