Clifford Constitution of 1922 - The system of government introduced as a result of the amalgamation of 1914 created sharp divisions between British officials and educated Nigerians on one hand, and between the chiefs and the educated elements on the other hand.

The euro area is a monetary union. In order to have a monetary union, there must be a situation in which at least two countries share the same official currency. In the euro area, this requirement is met. In other words, more than two countries have the euro as their official currency. Specifically, there are 19 states.