In 1846 he brought the subject of the American aborigines to the notice
of the members of Congress, expressing the opinion, and enforcing it by
facts drawn from many years' experience and residence on the frontiers,
that it was misunderstood, that the authentic published materials from
which the Indians were to be judged were fragmentary and scanty, and
that the public policy respecting them, and the mode of applying their
funds, and dealing with them, was in many things false and unjust. These
new views produced conviction in enlightened minds, and, during the
following session, in the winter of 1847, an appropriation was made,
authorizing the Secretary of War to collect the statistics of all the
tribes within the Union; together with materials to illustrate their
history, condition, and prospects. Mr. Schoolcraft was selected by the
government to conduct the inquiry, in connection with the Indian Bureau.
And he immediately prepared and issued blank forms, calling on the
officers of the department for the necessary statistical facts. At the
same time a comprehensive system of interrogatories was distributed,
intended to bring out the true state and condition of the Indian tribes
from gentlemen of experience, in all parts of the Union.

These interrogatories are founded on a series of some thirty years'
personal observations on Indian society and manners, which were made
while living in their midst on the frontiers, and on the data preserved
in his well-filled portfolios and journals; and the comprehensive
character of the queries, consequently, evince a complete mastery of his
subject, such as no one could have been at all prepared to furnish, who
had had less full and favorable advantages. In these queries he views
the Indian race, not only as tribes having every claim on our sympathy
and humanity, but as one of the races of the human family, scattered by
an inscrutable Providence, whose origin and destiny is one of the most
interesting problems of American history, philosophy, and Christianity.