First of all he did not find the sea route to the kingdoms of the far west as there there was another continent in the Great Ocean in the way about 2,000 km across the sea. Said continent was notable for being populated by a strange strain (or rather strains) of men. One which has an ancient civilization in which castes have been developed to a degree far beyond anything of any baseline human society. There are five castes in this society.
- Porters: 1.4 to 1.6 meters tall, 50-70 kilogram average weight. Both genders are broad shouldered, barrel chested, strong legs and have hard soled feat though they often are given simple sandals. Their most notable features have to do with their skulls in that the brain case has been reduced considerably. Porters are smarter than chimpanzees but dumber than a baseline human. Most of them can only speak a few hundred words and forming a rough sentence takes considerable concentration. Not that they are expected to speak much. Porters do simple brute force jobs such as mining and digging and carrying stuff about and pulling carts. They are also naturally docile and defer to others. The advantage of the reduced brainsize is the fact that they breed quickly, with a porter reaching physical maturity at age five, though they rarely live more than 40 years. They usually wear simple tunics, occasionally augmented by pants.
- Farmers: Averaging between 1.6 to 1.8 meters tall they have a build closer to the human baseline but they have long ears and a thin layer of fur. They have enlarged noses and pointed ears and a good sense of smell and brains possessing human level intelligence. Both male and female Farmers have considerable instincts in regards to caring and are well suited to tending crops and cultivating life. They are also cowards when it comes to violence.
- Artisans: 1 to 1.3 meters tall, 40-60 kg weight. They have long arms and short legs and a high level of dexterity and vision well adapted to fine detail work. Artisans tend towards impressionistic savantism. If they are introduced to a task at an early age they will become fascinated with said task, seek to master it and hone their abilities to a fine degree. They also serve as scribes, clerks and accountants. Like Farmers they are cowards in regards to violence.
- Mariners: 1.5 to 1.7 meters tall weighing 50-70 kg. They have a considerable layer of fat in their skin, no external ears, nicitating membranes and hair that does not grow more than 5cm from their heads. They have no nose but rather a set of nostril slits that can close and open at will. They can swim at up to 10km/h over short distances, hold their breath for up to 10 minutes and can easily swim kilometers. Their limbs are strong with feet with long webbed toes and webbed hands. They man the fishing boats, canal barges and logistical ships.
- Soldiers: 2-2.2 meters tall weighing in 130 to 160 kg. Both male and female Soldiers possess three times the average upper body strength of an average heathy human male. They have a heavily built body with broad shoulders and powerful muscles. Their skulls are thick and their brains have an extra layer of cushioning inside. Their skins grow a layer of hard scales over much of their body and their fingernails have been elongated to claws. They possess human level intelligence with quick reaction times and are raised from childhood in combat. Calmness under fire and discipline is a key characteristic. In battle they are usually clad in heavy steel armor (either lamellar or plate, often 2-3mm thick) and are armed with massive greatbows, three meter halberds, 2 meter long greatswords and 75cm warhammers.
- Administrators: 1.6 to 1.8 meters tall with a thin build, Administrators have slender builds, enlarged brains (about 1.5 times larger than that of a human baseline), reinforced spines and large eyes. If it was not for their coloration and hair people would often think of them as looking a bit like the classical grey aliens. Administrators have very good memories. Farmers, Artisans and Soldiers are programmed to recognize and obey Administrators (especially those that they have been conditioned to see as their immediate superiors) and hold them in deference. They are the Bureaucrats and Lords of this society, as well as the husbanders selecting individuals from the subordinate castes and breeding them to produce more formidable soldiers, more deft artisans, farmers better able to coax crops from the soil and more obedient porters. They also act as artists, architects, composers and designers. Administrators are notable in that they have an average lifespan of 130 years.
You wondered how much of that story was true until one day a fleet of five caravels came into your capital from the open sea with sails bearing strange geometric patterns. These proved to be manned by a crew of mariners, artisans and porters and carried payloads of Soldiers and a team of Administrators to speak to you in only slightly accented. Previously it had been believed that they lived on an globe which either A: possessed only one continent or B: possibly had multiple continents but all others beyond their own were so far away that attempting to reach them was suicide, but since the arrival of the foreigners they had changed their minds on the subject in light of evidence. As such they took notes when they repaired the explorer's ship an soon enough replicated it. They come on behalf of the 279th Triarchy of the state of Jianzotas Korzho and seek to investigate the opportunities and threats were offered by your realm.
Fortunately diseases which infect baseline humans and these creatures are different enough so they are not likely to cross over either way.
What do you do?