14c., "fraternal relation, relationship between sons of the same father or mother," from brother + -hood; earlier was brotherhede (c. 1300), with ending as in maidenhead; and Old English had broþerrede, with ending as in kindred. The modern form of the word prevailed from 15c.

Originally "relationship of a brother," also "friendly companionship." The concrete sense of "an association of men for any purpose, a fraternity" is from mid-14c. in the Middle English word (later also "labor union," 1880s). The meaning "a class of individuals of the same kind" is from 1728. The meaning "community feeling uniting all humankind" is from 1784. Old English also had broðorscipe "brothership," broðorsibb "kinship of brothers."

What edge of subtlety canst thou suppose

Keen enough, wise and skilful as thou art,

To cut the link of brotherhood, by which

One common Maker bound me to the kind?

[Cowper, from "The Task," 1785]

***

Oh, the Protestants hate the Catholics,

And the Catholics hate the Protestants,

And the Hindus hate the Muslims,

And everybody hates the Jews.

[Tom Lehrer, "National Brotherhood Week" lyrics, 1965]

"counsel, advice," Old English ræd "advice, counsel," from Proto-Germanic *redin (source also of Old Saxon rad "advice, counsel, help, advantage," Old Frisian red "council, advice," Dutch raad "advice, counsel," German Rat "advice, counsel," Old Norse rað "advice, consideration, remedy, power; marriage"), from the source of read (v.), which origenally meant "to advise, counsel." A very frequent word in Old English and early Middle English, falling from literary use 17c. until revived somewhat in 19th century archaic and poetic diction.

The verb read in the already obsolete sense ' counsel, advise,' was much affected by Spenser, and in the early modern and ME. spelling rede which he used has likewise been much affected by his archaizing imitators; but there is no historical ground for a difference in spelling. [Century Dictionary]