Revealing long-term trajectories of public opinion and polling in Britain: a new resource of historical data from the Gallup Poll in Britain, 1955–1991

From the 1930s to early 2000s, the British affiliate and later subsidiary of the Gallup Organization conducted around three thousand surveys of public opinion in Great Britain. While the records of the headline results of some of these polls can be found in Gallup’s monthly reports and news reports from the time, most of the individual level survey data were previously believed to have been lost. This article details how we have been able to reconstruct much of this important historical record, converting almost 800 survey datasets from 1955 to 1991 found in the archives of the Roper Center for Public Opinion Research. It first offers a brief overview of how the data were converted from the original column-binary format and what it reveals about methodological practices of Gallup in Britain. We then develop weights to improve the representativeness of the data across the entire time period, using the data to offer a number of insights into long-term trends in British public opinion.