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Aims: We examined differences in life span among the dominant tree species (spruce, Picea abies; fir, Abies alba; beech, Fagus sylvatica; and maple, Acerpseudoplatanus) across primary mountain forests of Europe. We asked how disturbance history, lifetime growth patterns, and environmental factors influence life span. Locations: Balkan Mountains, Carpathian Mountains, Dinaric Mountains. Methods: Annual ring widths from 20,600 cores from primary forests were used to estimate tree life spans, growth trends, and disturbance history metrics. Mixed models were used to examine species‐specific differences in life span (i.e., defined as species‐specific 90th percentiles of age distributions), and how metrics of radial growth, disturbance parameters, and selected environmental factors influence life span. Results: While only a few beech trees surpassed 500 years, individuals of all four species were older than 400 years. There were significant differences in life span among the four species (beech > fir > spruce > maple), indicating life history differentiation in life span. Trees were less likely to reach old age in areas affected by more severe disturbance events, whereas individuals that experienced periods of slow growth and multiple episodes of suppression and release were more likely to reach old age. Aside from a weak but significant negative effect of vegetation season temperature on fir and maple life span, no other environmental factors included in the analysis influenced life span. Conclusions: Our results indicate species‐specific biological differences in life span, which may play a role in facilitating tree species coexistence in mixed temperate forests. Finally, natural disturbance regimes were a key driver of life span, which could have implications for forest dynamics if regimes shift under global change. [ABSTRACT FROM AUTHOR]

• Current DBH distribution shapes are driven by historical disturbance regimes. • Low-severity disturbances showed a reverse J-shaped diameter distribution. • High-severity disturbance lead to a unimodal diameter distribution. • Time and severity of last disturbance are good predictors of DBH distribution shape. Natural disturbances strongly influence forest structural dynamics, and subsequently stand structural heterogeneity, biomass, and forest functioning. The impact of disturbance legacies on current forest structure can greatly influence how we interpret drivers of forest dynamics. However, without clear insight into forest history, many studies default to coarse assumptions about forest structure, for example, whether forests are even or unevenly aged. The aim of this study was to analyze the effects of past disturbances on the current diameter distributions of Norway spruce (Picea abies (L.) Karst.)-dominated landscapes throughout the Carpathian Mountains. Our dendroecological dataset comprises tree cores from 339 plots (7,845 total tree cores), nested within 28 primary forest stands, known to vary greatly in the severity of historical disturbances. Our analyses revealed that historical disturbances had a strong and significant effect on the current diameter distribution shapes at the plot level. We demonstrated that mixed-severity disturbance regimes were more frequent and create a complex pattern of diameter distributions at the plot and stand scale. Here, we show that high severity disturbance was associated with unimodal diameter distributions, while low and moderate severity was associated with the reverse J-shaped distribution. This is a result of complex disturbance patterns, with structural biological legacies. Our results will have important management implication in the context of tree size heterogeneity, biomass storage, and productivity as influenced by natural disturbances. Lastly, these results demonstrate that structural changes may arise as consequences of changing disturbance regime associated with global change. [ABSTRACT FROM AUTHOR]