What we know as the Parliament today had humble beginnings as the Governor General’s Council.

Regulating Act of 1773 : The Gov of Bengal was made Gov General of Bengal. He was assisted by 4 people. This 4+1 becomes became Supreme Council of Bengal (source), also known as the GG’s Exec Council.

Pitt’s India Act of 784 : We see a shrinking of the Council from 4 members to 3 members. Hence 3+1 is the renewed GG’s Executive Council. Can you tell us why? 

Charter Act of 1833 : Gov General of Bengal became the Gov General of India. The Supreme Council of Bengal became the Council of India. This Act. was the first law to distinguish between the executive and legislative powers of the Gov General. A 4th member was introduced who could only discuss and vote only on legislative matter.

Council of India = [(3+1) +  1(4th member also called the Law Member)]

The first such Law Member was Macaulay. This Council of India was, to a certain extent, the Legislature. Strength of the Executive remained 3+1 .

Charter Act of 1853 : From here on, we see a gradual increase in the membership of the Council and further separation of powers. The 4th member (Law Member)was included as a full-time Member in the GG’s Executive Council. His position was taken by 6 Members referred to as Legislative Councillors.

Council of India = [(4+1) + 6(Legislative Councillors) + 1 Commander-in-Chief]

6 Councillors were,

• 1 Chief Judge of SC of Calcutta.
• 1 Judge of SC of Calcutta
• 4 members of the ICS

Q. Who was the Commander-in-Chief?

Indian Councils Act of 1861 : After 1861, the Council was called Imperial Legislative Council(ILC) or Indian Legislative Council(ILC). The Executive was further enhanced by 1 member. The Viceroy now had the power to Nominate 6 – 12 Non-Official members in the Legislature who would be holding the office for 2 years.

ILC = [(5+1) + (Additional Members -> Minimum 6, Maximum 12)]

The composition of Additional Members was as follows:

• 50% Nominated Official Members
• 50% Nominated Non-Official Members

The Act thus sowed the seed  for the future Legislative as an independent entity separate from the Executive Council.

Indian Councils Act of 1892 : Due to the excessive demand of the Congress, the Additional Members were increased. Additional Members -> Minimum 10, Maximum 12.

ILC = [(5+1) + (Additional Members -> Minimum 10, Maximum 16)]

The composition of Additional Members was as follows:

• Nominated official members (those nominated by the Governor General and were government officials)
• 5 Nominated Non-Officials (nominated by the Governor General but were not government officials)
• 4 Nominated by the Provincial Legislative Councils of Bengal Presidency, Bombay Presidency, Madras Presidency and North-Western Provinces.
• 1 Nominated by the Chamber of Commerce in Calcutta.

Indian Councils Act of 1909 : The Morley-Minto reforms. It introduced for the first time the method of election.

The additional members of the Governor-General Council were  increased from 16 to a maximum of 60.

The composition of Additional Members was as follows:

• Nominated official members (those nominated by the Governor General and were government officials)
• Nominated non-official members (nominated by the Governor General but were not government officials)
• Elected Members (elected by different categories of Indian people)

Indian Councils Act of 1919 : The Montagu-Chelmsford Reforms. Central Legislature thereafter called the Indian Legislature was reconstituted on enlarged and more representative character.  It consisted of the Council of State consisted of 60 members of whom 34 members were elected and the Legislative Assembly  consisted of about 145 members, of whom about 104 were elected and the rest nominated.  Of the nominated members about 26 were officials.  The powers of both the Chambers of the Indian Legislature were identical except that the power to vote supply was granted only to the Legislative Assembly.

The Government of India Act 1935: It marked the next great stride in the evolution of the Legislatures.  The Federal Legislature was to consist of two Houses, the House of Assembly called the Federal  Assembly and the Council of States.  The Federal Assembly was to consist of 375 members, 250 to represent Provinces and 125 to represent the Indian States, nominated by the Rulers.  The representatives of the Provinces were to be elected not directly but indirectly by the Provincial Assemblies. The term of the Assembly was fixed as five years.  The Council of State was to be a permanent body not subject to dissolution, but one-third of the members should   retire   every   three   years.  It was to consist of 260 members.  104 representatives of Indian States, six to be nominated by the Governor-General, 128 to be directly elected by territorial communal constituencies and 22 to be set apart for smaller minorities, women and depressed classes.  The two Houses had in general equal powers but demands for supply votes and financial Bills were to originate in the Assembly.

• The information has been compiled from various sources, in case you find any discrepancy, please note it in comments.