Punjab Reorganisation Act, 1966

The Punjab Reorganisation Act was passed by the Indian Parliament on 18 September 1966, separating territory from the state of Punjab, most of which formed the new state of Haryana. Some was transferred to Himachal Pradesh, then a Union territory; while Chandigarh, the capital of Punjab, was made a temporary Union territory to serve as the provisional capital of both Punjab and Haryana. The larger state of Punjab had been formed under the States Reorganisation Act, 1956 by merging East Punjab and PEPSU. The 1966 separation was the result of the Punjabi Suba movement, which agitated for the creation of a Punjabi-speaking state (the modern state of Punjab); in the process a majority Hindi-speaking state was created (effectively, Haryana).

Within the Chandigarh Capitol Complex, the Palace of Justice hosts a sole Punjab and Haryana High Court as the common state supreme court for both states; the Palace of Assembly houses both the Punjab Legislative Assembly and the Haryana Legislative Assembly; and the Secretariat Building hosts the offices of the Chief Secretaries of both states. The state governors' residences, Punjab Raj Bhavan and Haryana Raj Bhavan, are next to each other on Sukhna Lake.