Laspeyres was the son of a law professor. He studied law and public finance at a succession of universities, gaining his PhD in political science and public finance from U Heidelberg. From 1874 to 1900 he was Professor of Political Science at Giessen U. He was an active member of the International Statistical Institute. He is remembered for the Laspeyres price index (see price index), though he was not the first to suggest its use and apparently did not use it himself.

http://faculty.arts.ubc.ca/ediewert/indexch4.pdf Fuller biography.