BACKGROUND: The continent of Europe has experienced remarkable changes in the past 25 years, providing scope for natural experiments that offer insight into the complex determinants of health. METHODS: We analysed trends in life expectancy at birth in three parts of Europe, those countries that were members of the European Union (EU) prior to 2004, countries that joined the European Union since then, and the twelve countries that emerged from the Soviet Union to form the Commonwealth of Independent States (CIS). The contribution of deaths at different ages to these changes was assessed using Arriaga's method of decomposing changes in life expectancy. RESULTS: Europe remains divided geographically, with an East-West gradient. The former Soviet countries experienced a marked initial decline in life expectancy and have only recovered after 2005. However, the situation for those of working ages is little better than in 1990. The pre-2004 EU has seen substantial gains throughout the past 25 years, although there is some evidence that this may be slowing, or even reversing, at older ages. The countries joining the EU in 2004 subsequently began to see some improvements in the early 1990s, but have experienced larger gains since 2000. CONCLUSIONS: Europe offers a valuable natural laboratory for understanding the impact of political, economic, and social changes on health. While the historic divisions of Europe are still visible, there is also evidence that individual countries are doing better or worse than their neighbours, providing many lessons that can be learned from.