We are seldom concerned about one important thing that occurred Marco Polo when he was hosted by the Emperor of China. So, why Marco Polo has become Marco Polo as we know him. The storytelling about him has usually been shallow and focusing only on certain details.
When the Mongols conquered the chinese territory, what was called China at that time, they established a society divided into four classes. The first, the upper class of course, was fullfilled by them, the Mongols. The second class was that of the coloured-eyes, definitely non-chinese people who are provided with coloured eyes, instead of chinese people who are (mostly) provided with black eyes. The third class was that of the chinese people. The fourth class, that one at the bottom of the graduation, was that of the non-chinese minorities.
Marco Polo had to give his fortune to the fact he was an individual belonging in the upper classes. In fact, he was a coloured-eyes class member.