Witty Rejoinder said:

The Rev Dodgson said:

captain_spalding said:

Also, you never know who else the people you encounter might have met, and what they might have learnt from them.

I know of a British chap who became lost in North Africa (vehicle breakdown, or similar).

He was on his last legs when he met an old Arab man, on a donkey or camel, can’t remember which.

The British bloke knew no Arabic, the Arab knew no English.

But, they both knew enough French to be able to communicate.

OK, but I’m pretty sure that nobody native to N America in 1492 could speak French.

Or even Latin.

Polyglots are probably the best people to act as interpreters for people who do not share any language simply because they have a wide experience of the various ways languages differ structurally which does impart knowledge of what meaning is imparted when translation of simple concepts are attempted between two groups.

What Witty said.

And, as i said, you have no way of knowing who ‘the natives’ may have met previously.

So, you take someone who knows as many as possible of the languages that you know about, to maximise your chances of communication.