Legally, [the European and US] notion of a corporation is very much the product of the European high middle ages. The legal idea of the corporation as fictive person...a person who, as Maitland the great British legal historian put it, 'is immortal, who sues and is sued, who holds lands, has a seal of his own, who makes regulations for the natural persons of who is composed' was first established in canon law by Pope Innocent IV in 1250AD, and one of the first kinds of entities it applied to were monasteries as also universities, churches, municipalities and guilds. The idea of a corporation as an angelic being is not mine, incidentally. I borrowed it from the great medievalist Ernst Kantorowicz who pointed out all that this was happening right around the time that Thomas Aquinas was pointing out that angels were really just the personification of Platonic ideas. According to the teaching of Aquinas, he notes, every angel represented a species. Little wonder then that finally the personified collectives of the jurists, which were juristically immortal species, displayed all the features attributed to angels.
The jurists themselves recognized that there was some similarity between their abstractions and the angelic beings. In this respect it may be said that the political and legal world of thought of the later middle ages began to be populated by immaterial angelic bodies, large and small. They were invisible, ageless, sempiternal, immortal and sometimes even ubiquitous, and they were endowed with a corpus intellectualae or mysticum -- an intellectual or mystical body -- which could withstand any comparison with the spiritual bodies of the celestial beings. All this is worth emphasizing because while we are use to assuming that there is something natural or inevitable about the existence of corporations in historic terms they are actually strange exotic creatures. No other great tradition came up with anything like it.-- from Debt: the First 5,000 Years by David Graeber.
See also Griffin.
P.S. an online seminar on Graeber here