Madra is the name of an ancient country as well as the communities inhabiting it in ancient Hinduism. Madra is referred to in Brihadaranyaka Upanishad. In his Ashtadhyayi (IV.2.108), Panini explains the process of formation of the compound words purvamadrah and apara madrah, one belonging to the eastern part of Madra and the other to the western part. Immediately following this sutra, he refers to certain villages lying to the north of the territory of the Madra. Thus it is obvious that Madra was the name of an area in ancient Punjab so considerably vast as to be divisible into two parts.
In another sutra (IV.2, 131), he says that the suffix kan is to be used with this word to bear out the sense of one born in Madra. It also shows that during the time of Panini, Madra was the name of a region considerably important on account of the people born there.
This is also borne out by the name of Madri in the Mahabharata; the princess belonging to this country was married to Pandu. Mention of the people of Madra in the Prayaga pillar inscription of Samudragupta amongst the people who acknowledged his suzerainty shows that this state was considerably assertive during his period and extended probably from the Ravi River in the east to Jhelum in the west. Patanjali was one of the famous scholars living there. He was so famous for his learning that students from distant places flocked to him.