PurposeThis paper aims to demonstrate how blog searching can be used as a retrospective source of public opinion.Design/methodology/approachIn this paper a variety of blog searching techniques are described and illustrated with a case study of the Danish cartoons affair.FindingsA time series analysis of related blog postings suggests that the Danish cartoons issue attracted little attention in the English‐speaking world for four months after the initial publication of the cartoons, exploding only after the simultaneous start of diplomatic sanctions and a commercial boycott.Research limitations/implicationsBlogs only reveal the opinions of bloggers, and blog analysis is language‐specific. Sections of the world and the population of individual countries that do not have access to the internet will not be adequately represented in blogspace. Moreover, bloggers are self‐selected and probably not representative of internet users.Originality/valueThe existence of blog search engines now allows researchers to search blogspace for posts relating to any given debate, seeking either the opinions of blogging pundits or casual mentions in personal journals. It is possible to use blogs to examine topics before they first attract mass media attention, as well as to dissect ongoing discussions. This gives a retrospective source of public opinion that is unique to blog search engines.