A student can only go for BA courses provided if he/she have passed 10+2 examination. Now as you didn't have qualified 10+2 then you aren't eligible for the course. As you have diploma you can join courses like BTech through lateral entry (if you have diploma in engineering) but you can't take admission to BA/BSc/BCom courses.

To know more about BA History visit the link below:

https://www.careers360.com/courses/bachelor-of-arts-ba-history

I hope this answer helps. All the very best for your future endeavors!

Hello dear
So as known the eligibility criteria for opting BA course is 10+ 2 exam Mark's  from a recognized board .

But there is chance to apply B.A history after completing your diploma in few universities, not all colleges provide this offer of doing BA after diploma ..but university like IGNOU and BHU ,Hyderabad university will offer !

But you have to qualify entrance exam given by  those universities.

So you  have chance to pursue BA history
So just go through those college websites and apply for it !
But think over again as your shifting from engineering to arts :)

Any queries feel free to ask!
All the best !