We have on Jatland Wiki entire book here -
An Imperial History Of India:
I quote from the book pp52-53
A great famine and invasion made the Eastern Provinces distracted, terrorised and demoralised.
In that country, undoubtedly, (then) there will be a king a great king of (An Imperial History Of India: End of page 52)
Mathura Jata (जाट) (Jat = जाट) family, born of a Vaisali (वैशाली) lady (T.), originally Vaisya . He became the king of the Magadhas (758-60).
महादुर्भिक्षसंपातं परचक्रसमाकुलम् ।
प्राच्या जनपदा व्यस्ता उत्रस्ता गतमानसा ।।758।।
भविष्यन्ति न संदेह: तस्मिं देशे नराधिपा: ।
मधुरायां जातवंशाढ्य: वणिक सूर्वी नृपो वर: ।।759।।
सोअपि पूजितमूर्तिस्तु मागधानां नृपो भवेत (T.463b)
तस्याप्यनुजो भकाराख्य प्राचीं दिशि समाश्टत: ।।760।।
तस्यापि सुत: पकाराख्य: प्राग्देशेष्वेव जायत: ।
क्षत्रिय: अग्रणी प्रोक्त: बालबंधानुचारिण: ।।761।।
Owing to the name Gupta the dynasty has been considered by the author as Vaisya originally. But the author is careful to note the fact in the next verse that they were described before him (prokta) as leading Kshatriyas (kshatriyah agrani) (क्षत्रियः अग्रणी) (761).
The invasion mentioned above refers to the Kota vs. Gupta fights for two generations.
It is to be marked that although the king is not named, he is described as the son of the Vaisali Lady in the Tibetan text. He is said to have been a Mathura-Jata (जाट) (Sanskrit- Jata-vamsa जाट-वंस) . Jata-vam'sa, that is, Jata Dynasty stands for Jarta, that is, Jat. That the Guptas were Jat, we already have good reasons to hold (JBORS, XIX. p. 115). His Vaisali mother is the Lichchhavi lady. Evidently the ancestors of Samudra Gupta, according to this datum, once belonged to Mathura. (An Imperial History Of India: p. 53)
My Note: We have to take into consideration the linguistic variations. In a country where there is no hard 't'(ट) we are left with no choice other than using soft 't' (त). So the Jat (जाट) being called Jat/Jut(जात)/(जत). जत becomes जर्त as Gujar (गुजर) becomes (गुर्जर) in Sanskrit.