Final answer:
The missing word in the provided context is 'indentured,' referring to indentured servants who played a significant role in labor supply for English colonists in America, often receiving land along with other dues after completing their service term.
Step-by-step explanation:
The missing word in the sentence 'But at what cost?' given the context provided is indentured. English colonists, like their Spanish rivals, faced challenges in producing agricultural goods and so they depended on indentured servants. These were European immigrants who signed contracts to work for a set period, usually between four to seven years, in the American colonies. In exchange for their labor, they received paid passage to America and sustenance. Upon completing their service, they obtained 'freedom dues,' which sometimes included land. This promise of a new life drew approximately 100,000 indentured servants to the Chesapeake Bay area during the 1600s, many of whom were young, impoverished men.
Indentured servitude was a crucial labor source in the English colonies, especially in the absence of the Carolina colonies' proprietors or under arrangements like those in Pennsylvania, where fifty acres of land were offered as a bounty for completing indenture service.