That was a restoration – usually capitals move when a government wants to build a new city, either as a vanity project, or to bring development to an underserved region or to minimise conflict between cities vying to be the capital.
Examples are the creation of Washington D.C. in 1790, Brazil’s capital Brasilia in the 1960s, Kazakhstan’s new capital Astana and Myanmar’s Naypyidaw.
Fear of Russian expansionism is rumoured to be one of the reasons the Kazakh capital was moved closer to the border (to deter an invasion), but the reasoning of the notoriously secretive Burmese junta is not completely understood.
The African continent has also seen two moves to purpose-built capitals – in Nigeria and Tanzania – while a third one in Cote D’Ivoire is considered incomplete by the U.N.
Another curious case of a capital move upon a change of political systems is the independence of Botswana in 1964. Previously, Mafeking had been the capital of the Bechuanaland Protectorate, which predated Botswana.
Astonishingly, the city was located outside the old protectorate and new state, prompting the move to Garborone.
Only one change of capital has taken place around the world because of environmental issues. In 1970, Belize’s new capital Belmopan was created after a hurricane destroyed the then-capital Belize City.
At least partially owed to environmental trouble, Indonesia has announced that it will move its capital from Jakarta to a new purpose-build location in the region of East Kalimantan on the island of Borneo by 2024.
The Indonesian leadership has cited the intent to help another region structurally the reason for the move, but observers also see burdens from pollution and overcrowding. Jakarta is also one of the fastest sinking cities on Earth due to its location below sea level and the excessive extraction of ground water.