Were shudras not allowed to learn Sanskrit in the past times? If yes, then around when did this practice of not being allowed start?
Various Śūdra and Dalit people have made contributions to Sanskrit literature, so they must have been able to learn Sanskrit to begin with, including the following -
King Śūdraka (apparently Śūdra caste) – composed Mṛcchakaṭika
Vidura (describes himself as Śūdra caste) – proclaimed the wisest person in Mahābhārata and taught Vidura-nīti
Vālmīki (supposedly Dalit/ Valmiki caste) – author of Ᾱdikāvya Rāmāyaṇa
Kālidāsa (Dalit according to folklore) – one the greatest Sanskrit language poets
It's not true, no one is barred from learning the Sanskrit language even by most orthodox standards. sanskrit was a language of common dialogue in past, so how were individuals supposed to use it without knowing it ?
The restrictions to be precise were on certain areas related to ritualistic practices like shruti scriptures in accordance with adhikara but that was for everyone to follow (not just one section). Other scriptures and literature was always available for everyone to study such as bhagwat gita, itihasas, smritis and other non religious literature.
Although, it's true that due to gradual decline in it's learning among commoners (which ever varna) newer dialects and then languages formed up like classical pali and prakrit etc. This process went further and created early Hindi dialects of middle age and then Hindustani of post independence era.
The *Brihaddharma Purana states
नचैवमाचरेत्धर्मं वैदिकं लौकिकं तथा। पुराणपठनं वेदपठनं नापि चाचरेत्॥ शास्त्रार्थकथनं चैव न शूद्रः क्वचिदाचरेत्। विप्रं क्षत्रं विशञ्चापि पाठयेन्न कदाचन॥ वर्णान् व्याकरणदीन् वा श्लोकं श्लोकार्थमेव वा। शूद्रो विद्यां ग्रहीतारं ब्राह्मणं पातयेदधः ब्राह्मणोऽपि पठन् शूद्रादात्मानमेव घातयेत्॥
Transliteration: (A Shûdra) shouldn't perform activities related to the Vaidika & folk practices. He should never read the Vedas & the Purânas. He should never discuss the meaning of the scriptures. A Shudra can't impart knowledge about alphabets, grammer, verses or their interpretations to Brâhmanas, Kshatriyas & Vaishyas. The Brâhmana who imparts knowledge to a Shûdra falls down (in hell) & the Brâhmana who gets knowledge from a Shûdra kill himself (i.e inflicted with the sin committing suicide).[Brihaddharma Purâna:Uttara Khanda:4:15-17]
Hence Shûdras are effectively barred from learning Sanskrit as
- They are prohibited to interpret & study scriptures written in Sanskrit.
- They are prohibited to impart knowledge (religious & secular) to people of other castes.
- Brâhmanas (de-facto custodians of education of that time) are prohibited to impart knowledge to Shûdras.
One can argue against these facts by pointing out to Shûdra characters conversing in Sanskrit in the epics & the Purânas but the evidence shows that these dictactes were the ones that were in practice. For example, Navadvîpa of my native state of Bengal was an important centre of Navya Nyâya. The identities of the various scholars of this school who studied in Navadvîpa has been compiled in the Samsad Bângalî Charitâbhidhâna. On going through the book, it was found that all of these scholars were Brâhmanas, not a single scholar was from non-Brâhmana background. Besides how can one explain the animal characters in these texts speaking in Sanskrit (for example conversation between a cat & a mouse with neither side having divine background, as stated by Bhishma as an example of forging alliance with enemies under mutually unfavourable conditions) ?
It was not before Ishvarachandra Vidyâsâgara opened the doors of the Sanskrit College of Calcutta to non-Brâhmanas in 1851 that Shûdras got the real oppurtunity to learn Sanskrit.