Regular population censuses are an integral part of the oversight functions of the modern state. Whereas the United Kingdom instituted a decennial enumeration in 1801, it was not extended to the overseas Empire. The administration of the British Empire was decentralised and early nineteenth-century census taking was subject to local initiatives. However, from the 1840s successive Colonial Secretaries considered a unified imperial census necessary to fulfil their oversight functions and demanded the taking of censuses by colonial governments to coincide with that in the United Kingdom. Initial responses were mixed, but with each decade the coverage improved, although no agreement was reached on the questions posed and the classification systems employed. These remained severe drawbacks to the creation of a comprehensive imperial view. Only in 1906 was an official volume entitled Report on the Census of the British Empire published. The experience gained in its preparation, collating the diverse colonial reports prompted the undertaking of a fully coordinated enumeration in 1911. The First World War intervened and prevented publication. Although subsequent attempts were made to revive the concept, little was achieved. The combination of the pursuit of local interests, accentuated by greater political independence, and the lack of adequate resources at the General Register Office in London to coordinate and analyse the results ensured that the quest for a unified census was finally abandoned with the onset of the Second World War. (C) 2007 Elsevier Ltd. All rights reserved.