A new Swedish population register, created by linking Census data to the Cause of Death Registry and covering over 99% of the population, has been used to study the relationship between occupational category, marital status and citizenship in 1970 and mortality in closely alcohol-related diseases during 1971-1980 for the ages 25-64 years. Age-standardized rate ratios (SRR) have been computed for mortality in alcoholism, alcohol intoxication and alcohol psychosis ("AAA") and in liver cirrhosis. SRR-values for both diagnose categories and both sexes were higher than average among not gainfully employed (SRR=3.71 among males and SRR=1.96 among females in 1976-80 for "AAA"), among employees in the service sector, engine-drivers and unskilled workers and increased in liver cirrhosis among artists and authors. Among females there were smaller variations in mortality for occupational groups than among males. The SRR-values showed a tendency to be higher in 1976-80 than in 1971-75, probably due to health-related selection to some extent. The alcohol-related mortality was also increased among divorced, widows (SRR=1.37 for "AAA" and 2.81 for liver cirrhosis in 1976-80) and widowers and among never married males. SRR was much higher among Finnish citizens in Sweden (SRR for "AAA"=3.85 among males and 2.35 among females in 1976-80) than among males and females living in Finland (SRR for "AAA"=1.13 among males and 0.36 among females) and also higher than among immigrants from other countries, summed (SRR for "AAA"=0.62 among males and 0.64 among females). The social distribution of mortality in "AAA" and in liver cirrhosis was similar. The new register could be a valuable tool for epidemiological studies and for health planning, as the participation rate is exteremely high, and as information about occupation and other social factors were collected prior to mortality.