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After India gained independence in 1947, a limited autonomy was conferred to New Delhi and was administered by a Chief Commissioner appointed by the Government of India. In 1956, Delhi was converted into a union territory and eventually the Chief Commissioner was replaced by a Lieutenant Governor. The Constitution (Sixty-ninth Amendment) Act, 1991 declared the Union Territory of Delhi to be formally known as National Capital Territory of Delhi. A system was introduced under which the elected Government was given wide powers, excluding law and order which remained with the Central Government. The actual enforcement of the legislation came in 1993.

In 1956, Delhi was converted into what type of territory?
a union territory