1n 1940, Tunku was appointed Deputy Director of Civil Defence, Southern Kedah. When the Japanese handed Kedah over to Thailand in 1941, Tunku was made Supervisor of Education, a post he held till the British took over Kedah and the rest of the country.  

Determined to complete his law studies, Tunku joined the Inns of Court in England in 1947. He received his legal qualification in 1949 and returned to Kedah.  

Soon after his return to Kedah, Tunku was made Chairman of the United Malays National Organisation (UMNO), Kedah. When Dato' Onn bin Jaafar resigned from his post of UMNO President, a delegation asked Tunku to accept the leadership of the party. Tunku became President of UMNO on the 26th of August, 1951.  

In the next few years, Tunku worked towards unity, traveling all over the country to speak to the people. His simplicity and warmth won the respect and affection of people from all communities and all walks of life.

His efforts and those of Chinese leaders, saw fruition in a political alliance of UMNO and the Malayan Chinese Association (MCA) in 1952; later was known as the Alliance Party. The Malayan Indian Congress (MIC) joined the Alliance in 1955.

The people of Malaya, as the country was called then, were sufficiently united to push for self-government in their progress towards independence. In July 1955, the first general election was held. The Alliance won 51 out of the 52 seats contested. Tunku was appointed Chief Minister and Minister of Home Affairs.

As Chief Minister, Tunku made a big effort to end communist terrorism in a peaceful way. On the 9th of September 1955, he declared an amnesty for communist terrorists who surrendered. As a follow-up, the Baling Talks were held on the 28th-29th December 1955 between the Malayan Communist Party, represented by Chin Peng, Chen Tien and Rashid Maidin; and the Government represented by Too Joo Hing, David Marshall, Tun Tan Cheng Lock and Tunku. The talks failed when Chin Peng rejected Tunku's proposal that the communists lay down their arms unconditionally. Tunku was more determined than ever to vanquish the terrorists. Five years later, the concerted effort of Malayans succeeded in ending the Emergency caused by communist terrorism.  

In 1956, Tunku led a delegation to London to hold talks with the British Government concerning independence for Malaya. The Malayan delegation, comprising of four representatives of the Malay Rulers and four Alliance representatives, convinced the British Government to set a date for independence: 31st August 1957.  

Achieving independence peacefully needed a great deal of wisdom and give-and-take. Tunku Abdul Rahman  and other leaders like Tun Abdul Razak, Dato' Sulaiman Abdul Rahman, Tun Tan Cheng Lock, Tun H.S. Lee and Tun Sambathan, made invaluable contributions to the Merdeka cause.

On the 30th of August 1957, at the Selangor Club Padang (now known as Dataran Merdeka or Independence Square), as the clock struck midnight the Malayan flag was hoisted to take the place of the Union Jack. Early the next morning, the 31st of August, at the Merdeka Stadium, Tunku read the Proclamation of Independence. On both occasions, Tunku's shouts of 'Merdeka!' were joyously echoed by thousands of Malayans who were there, and the millions who followed the proceedings through the mass media.  

Three years later, Tunku mooted the idea of Malaysia, to comprise Malaya, Singapore, North Borneo, Sarawak and Brunei. An inter-governmental committee was formed. On the 6th of January 1962, the governments of British and Malaysia set up the Cobbold Commission to find out how the people of Sabah (North Borneo) and Sarawak felt about joining Malaysia. The Philippines and Indonesia opposed the formation of Malaysia. Brunei made its decision not to join. On the 9th of July 1963, Malaysia was formed consisting of Malaya, Singapore, Sabah and Sarawak. Unfortunately, Singapore left Malaysia on the 9th of August 1965. The decision to let Singapore go was a sadness  for Tunku.

Just as Malaysia seemed securely set on a course of peace and prosperity, the race riots of May 13, 1969 jolted everyone into realizing that there were imbalances and rifts in Malaysian society, which must be corrected. Emergency was declared, Parliament suspended, and the country governed by the National Operations Council chaired by the Deputy Prime Minister, Tun Abdul Razak. On the 22nd of September 1970, Tunku, profoundly saddened by the May 13 Tragedy, stepped down, and Tun Abdul Razak became Malaysia's second Prime Minister.  

Tunku could not stop serving his beloved land. Through his newspaper columns, books and occasional speeches, he continued to emphasize the importance of national unity, religious tolerance and the eternal values of truth, justice, freedom and compassion among men.