A Quick History of Astral Projection

A while back on an occult books group, someone was looking for books in Latin about Astral Projection. Immediately I knew I'd not seen that term in any book old enough to be from the era of Latin writing. This led me to investigate when the first use of the term "astral projection" appeared in English.

Using Google Books, I saw little use of the phrase before the 1890s; though Atkinson's account of "Dream Psychomancy" bears some semblance to the phenomenon :

One morning in December, 1836, he had the following dream, or, he would
prefer to call it, revelation. He found himself suddenly at the gate of
Major N. M.'s avenue, many miles from his home. Close to him was a group
of persons, one of whom was a woman with a basket on her arm, the rest
men, four of whom were tenants of his own, while the others were unknown
to him. Some of the strangers seemed to be murderously assaulting H. W.,
one of his tenants, and he interfered. "I struck violently at the man on
my left, and then with greater violence at the man's face on my right.
Finding, to my surprise, that I had not knocked down either, I struck
again and again with all the violence of a man frenzied at the sight of
my poor friend's murder. To my great amazement I saw my arms, although
visible to my eye, were without substance, and the bodies of the men I
struck at and my own came close together after each blow through the
shadowy arms I struck with. My blows were delivered with more extreme
violence than I ever think I exerted, but I became painfully convinced
of my incompetency. I have no consciousness of what happened after this
feeling of unsubstantiality came upon me." Next morning he experienced
the stiffness and soreness of violent bodily exercise, and was informed
by his wife that in the course of the night he had much alarmed her by
striking out again and again with his arms in a terrific manner, 'as if
fighting for his life.' He, in turn, informed her of his dream, and
begged her to remember the names of those actors in it who were known to
him. On the morning of the following day (Wednesday) he received a
letter from his agent, who resided in the town close to the scene of the
dream, informing him that his tenant had been found on Tuesday morning
at Major N. M.'s gate, speechless and apparently dying from a fracture
of the skull, and that there was no trace of the murderers. That night
he started for the town, and arrived there on Thursday morning. On his
way to a meeting of magistrates he met the senior magistrate of that
part of the country, and requested him to give orders for the arrest of
the three men whom, besides H. W., he had recognised in his dream, and
to have them examined separately. This was at once done. The three men
gave identical accounts of the occurrence, and all named the woman who
was with them. She was then arrested, and gave precisely similar
testimony. They said that between eleven and twelve on the Monday night
they had been walking homewards along the road, when they were overtaken
by three strangers, two of whom savagely assaulted H. W., while the
other prevented his friends from interfering. H. W. did not die, but was
never the same man afterwards; he subsequently emigrated. (Vol. I. p.
142.)

In the past it's probable that these kinds of events would have been attributed to visions through dreams rather than through astral projection. The old time hoodoo concept  of "witches" who "ride" you when you sleep also seems to be considered as a practice achieved through something like astral projection. 

In fact, the oldest reference to astral projection I can find by that name is 1887, in a fictional book titled Mohammed Benani, where the concept is considered as "theosophy" -- an old word, but in this era usually associated with the Theosophical Society.