For most North Americans demography is an esoteric subject more often tied to marketing than to social and political changes. In Latvia, as in most of Eastern Europe and the USSR, demography has long been placed on the forefront of public attention. This wave of attention in the case of Latvia is not a fad of short duration which will be readily displaced by other popular topics. On the contrary, demography has had, is having and will have a tremendous impact on a very broad range of policies and on the long term survival of the Latvian nation. Thus, in order to understand the social and ethnic tensions, the labour squeeze, and the welfare burden of Latvia, it is necessary to understand the multifaceted demographic processes: the real matrix of the political and social environment. This paper reviews the pivotal demographic role of the First and Second World Wars and analyzes population size, sex balance, age structure, urban-rural residence, nuptiality, birth and death rates, migration patterns and ethnic balance.