Goodness, there was a huge amount of slavery, back into prehistory, then lots African slaves from the 6th century, then when Islamic conquest hit almost 1000 years ago many Indians were enslaved. Just as slavery was everywhere, it was in India. The big event was in 1843 when Britain did the moral thinking and emphasis to abolish it throughout their empire and also just in general, with British ships going to war against slaver ships and the British Empire buying slaves' freedom. The two big things about India and abolition were 1) the East India Company was definitely not as morally clear as the people in England, and 2) there was a worry that ending slavery in India would be too disruptive to the local culture, it was so embedded. So it was only abolished 10 years after the rest of the Empire.
Today, with 70 years of independence and self-rule, India has the most modern slaves in the world[0].
> Women are allowed to vote there.
Yes, as of 1950 when democracy was copied and pasted from other civilisations - some, like ancient Greece, almost 2000 years prior - who did all the discovery and moral thinking for this. It's not hard to copy something, particularly when declaring it to be so is what's measured, and not how well it's implemented.
[0] https://www.walkfree.org/global-slavery-index/country-studie...