One of the most significant developments in medieval Indian history was the growth of literature in regional languages. From about the seventh and eighth centuries, many North Indian languages such as Hindi, Punjabi, Bengali, Assamese, Odia (formerly called Oriya), Marathi, and Gujarati began to evolve rapidly from earlier Indo-Aryan Prakrits through the Apabhramsa stage. These languages gradually acquired distinct literary forms and became important mediums of cultural expression. In South India, Tamil, Kannada, and Telugu possessed much older literary traditions, while Malayalam emerged as an independent literary language only by the 14th century.

Hindi developed in several dialects such as Brajbhasha, Awadhi, Rajasthani, Bhojpuri, and Maithili. Its early phase, known as Adi Kala or Veergatha Kala, was marked by heroic poetry composed by court bards who glorified the valour and chivalry of Rajput rulers. Later, from the 14th–15th centuries, Hindi literature entered its most creative phase under the influence of the Bhakti Movement. Saints such as Kabir, Tulsidas, Surdas, and Mira Bai transformed Hindi into a powerful literary language by using the speech of common people to express devotion and social criticism. Sufi poets also enriched Hindi through mystical romances and cultural synthesis.

Alongside Hindi, Urdu developed as a composite language blending Khari Boli with Persian influences, especially under the Delhi Sultanate and later in the Deccan. Other regional languages such as Bengali, Punjabi, Marathi, Gujarati, Assamese, Odia, and the South Indian languages flourished through the Bhakti, Sufi, Jain, and courtly traditions. Together, the growth of regional languages democratised literature and reflected the cultural diversity of medieval India.