Actually, there were a number of stack machines that were pretty popular in the early days beyond Burroughs (which still exists). As mentioned, the HP3000's we

Actually, there were a number of stack machines that were pretty popular in the early days beyond Burroughs (which still exists). As mentioned, the HP3000's were stack machines and hugely popular. The ICL2600 and early Tandem machines were stack machines. And so was the Transputer, which still exists in various descendants. As to Algol, there's certainly a case that a stack machine is a nice abstraction for targeting an Algol compiler. However, having toyed around with writing an Algol compiler, I think the fact that it's a compact, well thought out language with an rigorously described syntax (BNF) that makes it relatively easy to attack, regardless of target.