Yes he was.
First, in regards to the issue of Peter in John 21:7, here is John Gill's commentary on the verse:
The Greek word (ependuthv), here used, is manifestly the (tdnwpa) of the Hebrews; and which, the Jewish writers say, was a strait garment, which a man put on next his flesh to dry up the sweat; and a very proper one for Peter, who had been toiling all night, and very fit for him to swim in; and, by what follows, appears to be put on him next his flesh: for he was naked; for to suppose him entirely naked, whilst fishing, being only in company with men, and those parts of nature having a covering, which always require one, was not at all indecent and unbecoming.
Also, the Greek word gymnos was used about Peter. This means a state of complete nudity. Peter was literally naked, though many translations hide this by saying it was just an outer garment he was taking off. This is using modern cultural mores to influence one's interpretation of history. Historical studies of the culture of the time indicate that public nudity was not at all unusual for fishermen, or for those working in the fields or in mines, even in cases when there were women present. Nudity in public was also not uncommon during athletic events. Hebrews 12:1 makes reference to this:
Wherefore seeing we also are compassed about with so great a cloud of witnesses, let us lay aside every weight, and the sin which doth so easily beset us, and let us run with patience the race that is set before us.
The author uses the analogy of a runner here, who would lay aside the garments that weighed him down, running naked. He is saying that, just as a runner strips himself of the garments that weigh him down so he can run, so we must strip off the sin that weighs us down. This is not an analogy that many people in our modern Christian culture are comfortable with, but the Christians in the early church would have understood the analogy just fine.
For those who say they "can't imagine" someone being crucified in a state of complete nudity in front of passers-by including women and children, I would say that how we imagine the past to be does not determine that is how it was. Nudity has been used in punishment throughout history. Defeated people throughout history had their clothing taken away to shame them. This shame was not the shame we have in modern times due to the mores that originated in the Victorian era, it was because to be denied clothing was the mark of a slave. Slaves that served well might be granted clothing, but it was not a given. Throughout the middle ages and even into early modern times nudity continued to be used in punishments. Even in Puritan New England, individuals were tarred and feathered on occasion. They would be stripped naked, have hot tar poured all over them, be coated with chicken feathers, and then be forced to sit on top of a rail and be paraded around town in that state before being dumped, naked and covered with tar and feathers, at the edge of town and told never to enter the town again. The problem with many people today is that things like this in history don't make them feel all warm and fuzzy and so they dismiss it due to their feelings. Well, feelings don't define the historical record, and if you think they do you are dabbling in the wrong field.