I have structured the post better and would appreciate if people can let me know what's wrong with this comment.
India is struggling hard to get rid of this menace introduced during colonial era. We have reservation in education, government jobs, and politics to bring backwards at par. Almost 50% of seats in education and government jobs falls under this category. Seat are also reserved into politics.
But the the irony of India is that caste as a system was introduced by European. Word caste itself is of Portuguese origin. Here is a quick read.[1]
All mature societies need skill based division of labour. India had Varna based system which meant society needs four classes of people to run smoothly. These weren't hard classes you were enforced in. People changes their classes as they changes profession. For example Rishi Vishmamitra was a born warrior but later on he turned into a academic. Here is a famous shloka from [2]
जन्मना जायते शूद्रः संस्कारात् द्विज उच्यते |
वेद–पाठात् भवेत् विप्रः ब्रह्म जानाती ब्राह्मणः |
Janmana jayate sudrah, samskarat dwij uchchte,
Veda pathnat bhavet viprah, brahma janati brahmanah
Meaning: In Vedic culture by birth everyone is Sudra(lower caste), by accepting Samskara (Purificatory process) one becomes a Dvija(Twice Born), By study of Veda one becomes Vipra, Knower of Brahman is Brahmana. It means a true brahmin has the divine vision, knowledge and powers.
Sloka means everybody is born a Sudrah. One who follows the right samskaras has a second birth, one who reads the vedas and understands them becomes a wise man and one who realises the brahma or the source of creation becomes a Brahman. Those seven mind born Rishis of Brahma are real Brahmins ancestors- parents of humen.
In brief, all knowledge work was supposed to be handled by academic class Brahmins. Being born in a Brahmins family wasn't enough to get you into academics though. If you became a warrior you will be called kshatriya. Similary business class vaishya, and Shudras class existed to take care of rest of the social functions and creative endeavours. Profession like engineering, arts, temple building, city planning were all done by the 4th class.
I would argue this isn't any different from today. In order to become professor or researcher(Brahmin) you need a qualification. In order to become a soldier you need to join army. Entrepreneurs and business people drive the world of commerce. Similarly rest of the professions exist too.
Colonial Europeans turned this system into rigid caste based system. which slowly changed over to rigid system as society went into preservation mode as noted by dilippkumar in a comment.
India was the only society without slavery as noted by various travellers. Until English colonial forces destroyed it systematically, India had an education system in which major beneficiary were the so called lower caste of today. Here is another short summary with further references.[3]
[1] https://scroll.in/article/882736/caste-system-in-india-has-i...
[2] https://qr.ae/pN4tBC (Skanda Purana Vol.18 Book VI , Nagar Kanda , Chapter 239 , Verse 31-34)
[3] http://www.indianscience.org/essays/DHARAMPALINTRODUCTION(Pa...