Municipal consolidation

A merger, consolidation or amalgamation, in a political or administrative sense, is the combination of two or more political or administrative entities, such as municipalities (in other words cities, towns, etc.), counties, districts, etc., into a single entity. This term is used when the process occurs within a sovereign entity.

Unbalanced growth or outward expansion of one neighbor may necessitate an administrative decision to merge (see urban sprawl). In some cases, common perception of continuity may be a factor in prompting such a process (see conurbation). Some cities (see below) that have gone though amalgamation or a similar process had several administrative sub-divisions or jurisdictions, each with a separate person in charge.

Annexation is similar to amalgamation, but differs in being applied mainly to two cases:

The act of merging two or more municipalities into a single new municipality may be done for a variety of reasons, including urban growth, reducing the cost of local government and improving the efficiency of municipal service delivery.

In 1977, the 2,359 municipalities of Belgium were merged to 596 new municipalities.

In 1975, the state of Guanabara and the state of Rio de Janeiro in Brazil were merged. The former consisted of only the territorial limits of the city of Rio de Janeiro, formerly the Federal District as Brazilian capital until 1960, when it was moved to newly built Brasília. When merged, Guanabara became the municipality of Rio de Janeiro within the new state. In geographical terms, it would seem the state of Rio would have incorporated Guanabara; but, as the administrative and financial resources of the former capital were significant and even larger than the rest of the state, the change was more correctly referred to as a merger (fusão).

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