China sponsored Marco Polo's exploration.
He didn't represent any country. Polo was a 17 year old young man who left Italy with his father a Venice merchant to establish trade with China. It took them 4 years to reach it.
Italian Trader
*
Italy
Marco Polo had never been to Japan, but he did write about what he heard about the country while he was in China. Marco Polo called Japan Cipangu, which means 'the country of Japan' in Chinese.
Italy
Spain :)
Marco did not sail for a country
china
Italy
vinice