Previous research may have failed to find a general relationship between war and techno-scientific activity due to the failure (a) to treat the various types of war separately and (b) to use yearly rather than generational time series. Hence, the present study examined 404 consecutive years in European civilization from 1500 to 1903. Measures of four distinct kinds of war were defined and a log-transformed measure of techno-scientific activity was derived from a factor analysis of six histories and chronologies. The techno-science measure was regressed on the war measures plus a set of control variables. Techno-scientific activity was found to be a negative function of balance-of-power and defensive wars fought within Europe. In contrast, imperial and civil wars exerted no influence.