Estimating continuous local and regional historical populations from marriage records. A case study in the Barcelona area, 1451-1860

Anna Cabré, Universitat Autònoma de Barcelona
Joana-Maria Pujadas-Mora, Universitat Autònoma de Barcelona
Miquel Valls Fígols, Universitat Autònoma de Barcelona

As ancient censuses are scarce or non-existent, estimating past populations is necessary for many historical research purposes. The Barcelona Historical Marriage Database (BHMD), built through the on-going ERC Project Five Centuries of Marriages, provides a continuous series of marriages for 90 parishes in the Barcelona area allowing population estimates under the assumption of constant marriage rates in time and space. Our goals are three: a) discussing the ideal fixed marriage rate to be used as an estimating tool; b) establishing the yearly populations of each of the 90 parishes from 1720 to 1860; and c) estimating populations for Barcelona and for Catalonia since 1451. a) Observed marriage rates have been calculated for the area using the population figures from the censuses of 1787 and 1860. These rates have been applied to the average yearly marriages in each parish; the populations so estimated have been compared to their counterparts in the Census, showing striking coincidence. Thus, the assumption of spatial homogeneity has been accepted. As for time variations, rates calculated at every census from 1787 to 1970 show that marriage rates do not sensibly differ from 9 per thousand, accepted as our technical fixed marriage rate. b) All local populations have been estimated from 1720 to 1860, because parish assignation was unclear before 1720 and frequent censuses were available after 1860. Results are shown in maps and graphs. Time-trends been analyzed in search of consistency. c) The rough historical data available since the 15th century suggest a surprising stability, until 1860, in the proportions between the city of Barcelona, our area of study and the whole Catalonia. Therefore, since the BHMD starts in 1451, we are presently estimating continuous populations for Barcelona and Catalonia. Comparison with occasional data mentioned in literature promise satisfying results.