Poincare defined the fundamental group and the homology groups and proved that H _1 was pi _1 abelianized. So the question came up whether there were other groups pi _n whose abelianization would give the H _n. Cech defined the higher pi _n as a proposed answer and submitted a paper on this. But Alexandroff and Hopf got the paper, proved that the higher pi _n were abelian and thus not the solution, and they persuaded Cech to withdraw the paper. Nevertheless a short note appeared and the pi _n started to be studied anyway...
Taken from http://www.intlpress.com/hha/v1/n1/a1/ ,page 17
