Discuss the major issue which led to the formal split of the Congress Party in 1969.
The major issue that led to the formal split of the Congress Party in 1969 was the defeat of the official Congress candidate in the Presidential election. This defeat formalised the split in the party. Following this, the Congress President expelled the Prime Minister Indira Gandhi from the party, and she claimed that her group was the real Congress.
By November 1969, the Congress group led by the 'Syndicate' came to be referred to as the Congress (Organisation) or Old Congress, while the group led by Indira Gandhi came to be called the Congress (Requisitionists) or New Congress. Indira Gandhi projected the split as an ideological divide between socialists and conservatives, and between the pro-poor and the pro-rich.
Explanation
The context clearly identifies the defeat of the official Congress candidate in the Presidential election as the immediate cause that formalised the split. The Syndicate had supported the official candidate, while Indira Gandhi had backed V.V. Giri (implied by 'defeat of official candidate'). The context also mentions how Indira Gandhi framed this split ideologically to gain political advantage.