Yes, sovereignty was a big issue for a lot of people.
So was racism, but not necessarily in the way a lot of people understand it nowadays. My parents are in their 80s, and neither of them has any issues with the Black or Brown people they've worked with over the years, or with the carers from those groups they've had more recently. What they do have, and always have had, is a lasting distrust of Germans and a bone-deep, almost genetic, contempt for and loathing of the French! That was a motivating factor for many, especially those who served or grew up in WW2.
That goes back to 1066, when our last English King was deposed, opening the way to a succession of French rulers who were eventually replaced by the current bunch of Germans!
As to history, my own studies have led me to the conclusion that every time Britain has allowed itself to be caught up in the affairs of Europe, it has ended up costing us, in lives and economically. WW2 was the last straw, and we've been struggling ever since.
I voted to leave the EU because I am sick and fed up to the back teeth of the UK still pretending to be a global Power. Our day has gone, America is waning. Power, progress and energy have passed to the Pacific Rim, including Australia and New Zealand, and will soon start to burgeon in Africa. Time for us to leave alone and hopefully be left alone.