Once upon a time there was East Pakistan and West Pakistan, but it was supposed to be one country because its basis of creation was not ethnicity but religion.
The population of East Pakistan was 53% and West Pakistan was 47%. Naturally, the total number of seats in Parliament were divided up proportionately and East Pakistan had more seats than all of West Pakistan. When the 1970 elections results came in, Sheikh Mujib ur-Rehman's Awami League had won every seat in the National Assembly from the East except TWO: Maulana Bhashani, and Nur ul-Amin were the ONLY two who got elected and were not of the Awami League (Maulana Bhashani, decided to stay in Bengal. Nur ul-Amin sided with the military government.)
The math worked out such that Mujib ur-Rehman had a total majority in the National Assembly and therefore did not need any coalition partners to form the government.
No one had anticipated such a landslide. No body thought he would win an overall majority because his party did not field any candidates in West Pakistan. Abdul Vali Khan (Ghaffar Khan's son) was his nominal ally in the West and had no candidates in the East. Any way, when the results came in the bigotted Islamabad establishment started having nightmares about dark, short, fish-and-rice eaters from Bengal becoming their bosses. Of course, they were going to destroy "our Pakistan". Weren't they Hindu sympathizers any way? Had they not said that they will institute Bengali language (which is a language of kafirs because it is written like hindi) in their schools and Urdu was going to be abolished? And was it not Hazrat Quaid-i-Azam Rehmat-ullah-Elah's command that Urdu was sacred to Pakistan. How dare that upstart "traitor" think he was going to be our Prime Minister? How dare he aspire to occupy the office once inhabited by our beloved Shaheed-i-Millat. etc., etc.
After the election results were confirmed and a week passed, there were calls for convening the National Assembly session so that the new parliament could be sworn in and the government formed. There was, in the mean time, a flurry of activity in the Rawalpindi GHQ at the end of which the military dictator of Pakistan, general Agha Mohammed Yahya Khan changed the rules of the game.
He said that the Assembly will be called into session within 90 days, and then it will first have to form a new constitution within 90 day, and only AFTER that will a date be fixed for the transfer of power to the new government. If the Assembly failed to pass a new constitution (i.e., with 66% votes), then it will be dissolved. In the mean time, he decreed, martial law will rule supreme.
Understandably, Sheikh Mujib ur-Rehman was furious and declared Yahya Khan a usurper and announced that he will call the parliament into session any way. He said that the new National Assembly will hold its first session in Decca and proceeded to invite all the elected Assembly members from Punjab, Sindh, NWFP and Balouchistan to come and attend the Assembly and defy the illegal military government. Thus began the crisis.
Zulfikar Ali Bhutto who should have been leader of the opposition in the united Assembly, could be the majority leader Iand thus PM) if the Bengalis were not counted. He conveniently sided with the military and declared that he will "break the legs" of any MNA who goes to Decca. Yahya Khan declared the proposed session to be held in Decca as illegal and threatened to disqualify all those who attended it.
To cut the long story short, Yahya Khan hurriedly started transferring troops to Bengal and began preparation for a crackdown while engaging Mujib in negotiations to delay the crisis. Zulfikar Ali Bhutto was a party to the negotiations.
Yahya then declared that, "...the man (Mujib ur-Rehman) and his followers are TRAITORS and ENEMIES of Pakistan..." (I heard that speech, those fateful words still reverberate in my ears) and disqualified the legitimate representatives of the majority of the country's populations. Thus a new historical precedent was established where 53% of the population were denounced as "traitors". Those "traitors" were the majority of the population of the country that once upon a time existed.
Mujib ur-Rehman was arrested and put in Multan jail. We were told that he had been a long standing Indian agent who was previously involved in the Agarthala conspiracy. (Agarthala, by the way, was another cruel joke but that was played by another general who promoted himself, like Idi Amin Dada did, to the exalted rank of Field Marshal.)
General Yahya called the rump parliament into session and staged a travesty which made Pakistan the laughing stock of the world. Nur ul-Amin, who was the only Bengali MNA and represented a party that won only one seat in the National Assembly, was made Prime Minister. The poor fossil was a thousand years old, could hardly stand up unaided. Zulfikar Ali Bhutto was made Deputy Prime Minister and Foreign Minister and we were told that all is well. Then the Pak Fauj proceeded to kill thousands of its own citizens. The civil war began.
The Pak Fauj, with its brutal intelligence appartus systematically murdered doctors, lawyers, professors, journalists, students and intellectuals who were deemed to be enemy sympathizers and traitors - "traitors" indeed . Many of our Pak Faujis, raped, pillaged and wantonly slaughtered civilians, only because they were, on average, darker and shorter, ate fish-and-rice instead of dal-roti and spoke Bengali, not Urdu. That is what made them "traitors"!
Hundreds of thousands of Bengalis fled for their lives and crossed the border over to Hindustan. India saw a perfect opportunity and got involved and Pak Fauj got pulverized and ignominiously surrendered en mass on December 16, 1971.
Yahya Khan was deposed by Lt. Gen. Gul Hassan, and Air Marshall Rahim Khan, who summoned Bhutto and, on December 20th, hurriedly made him President and chief-martial-law administrator after the war ended in the West. Bhutto continued the travesty by appointing the semi-comatosed Nur ul-Amin his Vice President. Mujib languished in jail for months longer.

