c. 1300, "in a state of a serf, unfree," from bond (n.) "tenant, farmer holding land under a lord in return for customary service; a married bond as head of a household" (mid-13c.). The Old English form was bonda, bunda "husbandman, householder," but the Middle English word probably is from Old Norse *bonda, a contraction of boande, buande "occupier and tiller of soil, peasant, husbandman," a noun from the past participle of bua, boa "to dwell" (from PIE root *bheue- "to be, exist, grow").
"In the more despotic Norway and Denmark, bo'ndi became a word of contempt, denoting the common low people. ... In the Icelandic Commonwealth the word has a good sense, and is often used of the foremost men ...." [OED]. The sense of the noun deteriorated in English after the Conquest and the rise of the feudal system, from "free farmer" to "serf, slave" (c. 1300) and the word became associated with unrelated bond (n.) and bound (adj.1).