Bengal was a country located in the Ganges delta.
In 1201 (or 1204?), Muslims started attacking Bengal, conquering it during the next decades, ending the Sena dynasty.
Then however, another power rose in the East - Hong China. In 1492 (3189, Yang Water Rat in the Chinese calendar), the sultan of Bengal paid tribute to the Hong.
Soon after, in 1502 (3199, Yang Water Rat), the "Betrayal of Bengal" happened: After the sultan of Bengal requested military and technical advisors from the Hong, who helped him to equip his army with cannons, he stopped paying tribute. Chinese traders were ousted from Bengal. In return, a border war in Arakan broke out, during 1516-18. Bengal was defeated by Hong vassals, had to retreat and pay tribute again.
1779, Italy made a trading treaty with Bengal, which gradually came under the influence of the former.