Mahatma Gandhi declared that Swaraj would not come for a hundred years if,

Mahatma Gandhi declared that Swaraj would not come for a hundred years if, untouchability was not eliminated.
Mention the efforts of Gandhiji to get Harijans their rights.

For long period, the Congress had ignored the Dalits for fear of offending the conservative high caste Hindus. For the first time, Gandhiji called the untouchables as ‘Harijans’ or the children of God.
Efforts of Gandhiji for Harijans
Gandhiji organised Satyagraha to secure the entry of the untouchables into temples and access to public wells, tanks, roads and schools.
Gandhi himself cleaned toilets to dignify the work of the bhangi (the sweepers) and persuaded the upper caste to change their heart and give up the sin of untouchability. Gandhiji signed Poona Pact (September 1932) with Dr Ambedkar. It gave the depressed classes reserved seats in Provincial and Central Legislative councils, but they were to be voted in by the general electorate.