Gish was born in White City, Kansas in 1921, so he was a young lad when the famous Scopes Monkey Trial took place in 1925. He was raised Methodist, but he became a fundamentalist Baptist later on. Gish earned a PhD. in biochemistry from Berkeley in 1953, and after reading creationist materials in the late 1950s he began to get involved in the YEC crusade. He was one of the best known figures for YEC debating scene, best known for putting out a large number of statements in quick succession that his opponent almost certainly could not refute in the time allotted. This has become known as the Gish Gallop, and it has been noted as a technique used by others in a debate: throw out many arguments, your opponents will be able to deal with only so many and not adequately, and you can claim one of your un-refuted arguments stands and that means you are right.
Gish also worked at the Institute for Creation Research (ICR), which was the largest creationist organization until AiG surpassed it. In a more humorous context, Gish was part of the story of Dave Gorman and following his Googlewhacks, which is a great comic adventure and live performance. Gish is survived by his wife, Lolly, four children, and several grandchildren according to AiG.
RationalWiki blog has more on Gish, but I have mentioned him here before. In my post about proponents of creationism being liars, I used Gish as an example. He had used the argument that the Bombardier beetle could not have evolved without going through a stage in which it would have exploded. He was proved to be false, he admitted his argument wasn’t right, but he did continue to use that same argument (and it gets repeated to this day by others). But even though there is one less Liar of Jesus out there, there are plenty to take his place; then again, it’s hard to get a YEC with decent academic qualifications rather than ones just made-up.