Squanto

   Squanto played a very important role to the English colonies.  He was brought to the colony by another Indian named Samoset, who could speak very broken and bad English.  Samoset told the English that Squanto could speak English well, since he had been to England.  He helped the Pilgrims negotiate peace treaties among the Indian tribes and create trading agreements.  He helped translate and negotiate between the governors and tribal leaders.  He also worked as a guide to the Pilgrims, by teaching them about how to utilize their natural resources that were new to them.  I believe that the Pilgrims probably would not have survived without Squanto.  The Indians may have attacked the English if there was no peace treaties. The may have all died of starvation if they were not able to trade with the Indians, or if Squanto had not taught them about the land.   
Source: http://www.mayflowerhistory.com/History/BiographyTisquantum.php
Picture: http://www.east-buc.k12.ia.us/01_02/AH/sq/sq.jpg1