Much more ancient
We find mention of Jat in Mahabharata.
Mahabharata Shalya Parva section 45 says, "Listen now to the names of those other combatants armed with diverse weapons and clad in diverse kinds of robes and ornaments, that Skanda procured: ....Akshasantarjana, Kunadika, Tamobhrakrit, Ekaksha, Dwadasaksha, Eka Jata ... Beholding the installation of Kartikeya, These and many other mighty companions, O king, came to the high-souled and illustrious Kartikeya". <ref>[
http://www.sacred-texts.com/hin/m09/m09045.htm Mahabharata Shalya Parva section 45]</ref>This has been illustrated in following shlokas in the online edition of Mahabharata in Sanskrit alongwith Devanagari as under:
:अक्षसंतर्जनॊ राजन कुनथीकस तमॊ ऽभरकृत akṣasaṃtarjano rājan kunadīkas tamo 'bhrakṛt <ref>[
http://www.sacred-texts.com/hin/mbs/mbs09044.htm Mahabharata in Sanskrit Ch-44/53]</ref>
:एकाक्षॊ थवाथशाक्षश च तदैवैक
जटः परभुः ekākṣo dvādaśākṣaś ca tathaivaika jaṭaḥ prabhuḥ <ref>[
http://www.sacred-texts.com/hin/mbs/mbs09044.htm Mahabharata in Sanskrit Ch-44/54]</ref>
The Jat historian [[Dharmpal Singh Dudee]], has explained the above mahabharata legend, in which Brahma nominated Swami Kartikeya as senapati of all the beings and performs his coronation on this position. On the occasion of coronation, Swami Kartikeya received various offerings from manifold people. One of these was a chief of all the senapatis (generals) named Jat. <ref>Dr Mahendra Singh Arya, [[Dharmpal Singh Dudee]], Kishan Singh Faujdar & Vijendra Singh Narwar: Ādhunik Jat Itihasa (The modern history of Jats), Agra 1998 , Page 2</ref> This shloka reads in [[Sanskrit]] as under:
अक्षः सन्तर्जनो राजन् कुन्दीकश्च तमोन्नकृत।
एकाक्षो द्वादशक्षश्च तथैवैक
जटः प्रभु ।।
Translation- O Rajan! Akshaḥ santarjana, kundīka, tamonnakrata, ekāksha, dwādashāksha and a 'Jat' the chief lord offered to Swami Kartikeya.
Thus appearance of Jat name in Mahabharata along with Brahma shows that name of Jat is as antique as Brahma.<ref>Dr Mahendra Singh Arya, [[Dharmpal Singh Dudee]], Kishan Singh Faujdar & Vijendra Singh Narwar: Ādhunik Jat Itihasa (The modern history of Jats), Agra 1998 , Page 2</ref>
The famous Sanskrit scholar Panini of 900 BCE has mentioned in the Sanskrit shloka as
जट झट संघाते Jat Jhat Sanghate
This means Jat is a democratic federation. He has mentioned about many Jat tribes settled in Punjab and North west areas.
The Arabian traveller Al-biruni has mentioned that Lord Krishna was a Jat.
The next mention we have of Jats is in the sentence in the grammar of Chandra of the fifth century as under:
अजय जर्टो हुणान Ajay Jarto Hunan
This means that Jats conquered Huns. This inscription of Mandsaur also indicates that Yasodharman, the ruler of Malwa, was a Jat.