I am trying to find out when in history grape juice or non-alcoholic wine was first used?
I'm sure the "Ancients" drank grape juice. It was probably a delicious treat when it was in season when the grapes were ripe in the Fall. I love drinking the juice from my wine grapes, it's very good! But, without filtration or sulfites, there was no way to store grape juice without spontaneous fermentation, even after boiling it. Eventually something would turn it into wine or vinegar. So, you always ended up with wine whether they wanted it or not. So, yes, they probably drank grape juice, but only for a short period after harvest time.
The method of pasteurizing grape juice to halt the fermentation has been attributed to an American physician and dentist, Thomas Bramwell Welch in 1869. A strong supporter of the temperance movement, he produced a non-alcoholic wine to be used for church services in his hometown of Vineland, New Jersey.
Of course, simple grape juice, that you'll get by just pressing grapes, is probably used much much longer.