Official Finnish population statistics starting in 1751 do not provide cross-classifications of age and marital status before 1880. However, declining overall proportions married and declining fertility rates suggest a major change in the marriage pattern during the second half of the eighteenth century. Five sources of information, namely overall proportions married, annual numbers of marriages, sizes of marriage cohorts relative to mortality-adjusted birth cohorts, information on the modal age at marriage from lagged correlation analysis between sizes of birth and marriage cohorts, and trends in age-specific fertility are analyzed to provide information on nuptiality trends. A simulation model based on the Coale-McNeill marriage model yields parameter estimates for the Finnish provinces in 1751-1772, which allow calculation of the "Princeton Index" I_m.
The results suggest a "nuptiality transition" from early and almost universal marriage to the so-called "European Marriage Pattern", which is characterized by late marriage and high proportions of unmarried. Provincial level analysis reveals significant east-west differentials with higher proportions marrying and lower mean ages at marriage in the eastern parts of Finland. Non-quantitative historical evidence in general also supports the assumption of a major change in the Finnish nuptiality pattern during the second half of the eighteenth century