In 1953 Greenland's colonial status ended with the establishment of the 1953 Danish constitution. When the colonial status ended, Greenland was incorporated into the Danish realm as a Amt (county) which gave Greenlanders Danish citizenship, as a result of this, a change in Danish policies toward Greenland that consisted of a strategy of cultural assimilation. During this period, the Danish government promoted the exclusive use of Danish in official matters, and required Greenlanders to go to Denmark for their post-secondary education; many Greenlandic children grew up in boarding schools in southern Denmark, many losing their cultural ties to Greenland. The policy also backfired to produce a reassertion of Greenlandic cultural identity by the Greenlandic elite, leading to a movement in favour of independence that reached its peak in the 1970s; because of this, a further desire to establish the legality of Greenland's status formed in Denmark, resulting in the Home Rule Act of 1979, which gave Greenland limited autonomy with its own legislature taking control of some internal policies, while the Parliament of Denmark maintained full control of external policies, security, and natural resources. The law came into effect on 1 May 1979.