The name John Jones is the first to be found in the legal records of Oxford.
The case is fairly early [Bundle 7/ No.13] which begins 1458. No reasons were listed for the case. Remember, this is for the county of Oxford, and for the University. The first JONES to attend Oxford University is a "Richard Joonys" 1505. I suspect that poor old John is close to 50 years before.
For additional comments see posts [The Jones Surname] 28 Sept. 2011, 9 Oct. 2011, and 6 Feb. 2015.