Here's a map of the Straits Of Malacca, I've been through there a few times and it is highly infected with pirates, even today.
The area (Malaysia)above the Straits is the oldest rain-forest in the world at 130 million years. That rain forest was there when the Indian continent went trucking by 50 million years ago and crashed into the land mass and created the Himayalian mountains.
This area must have been a perfect place for humans to live, flourish even, during the Ice Age.
Some of the oldest human DNA ever discovered is in Malaysia with some small Negrito people.