It was 1957, and the field of Programming Languages was at its infancy. Heck, the field of Computer Science was barely out of the womb. But the first FORTRAN compiler had recently been implemented, and proved to the world that high level languages were feasible.
It was in this year, 1957, that two groups of programmers, one group in Europe and the other in the US, began an ambitious project to design the next-generation high-level language called ALGOL, short for Algorithmic Language.The programmers at that time had a "gentleman's agreement" that nothing would be added to the design of the language unless it was known to be implementable.
The culmination of this work came out in 1960 in a document now known as the Algol report. For the first time, the syntax of a whole programming language was described in a formal language (the BNF, or Backus-Naur Form). The semantics of each programming construct was also defined, albeit in a less formal language: English. As early as the fall of 1960, Dijkstra already had an implementation of Algol 60.
In the years ensuing, there was a great deal of debate about the ambiguities of the report. In 1962, after having the control of Algol transferred to a "Working Group" under the IFIP (International Federation for Information Processing), a revised report came out correcting the more obvious mistakes of Algol 60. And, in 1968, after much controversy, the Algol 68 report came out.
C.A.R. Hoare said this about Algol 60: "Here is a language so far ahead of its time, that it was not only an improvement on its predecessors, but also on on nearly all its successors." Apparently referring to Algol 68, and PL/1.
Algol was never a popular language outside academia. Much (perhaps underserved) criticism is heaped on Algol, that the language is too big, too complex, too difficult to implement. On a practical scale, Algol also never had a good I/O system specified. Whatever its deficiencies though, Algol gave us:
But perhaps most importantly, Algol allowed us to think about programming language design as itself, an important and interesting area of study.
P. Wegner, Programming Languages -- The First 25 Years, IEEE Transactions on Computers, Dec 1976
John A. N. Lee, Programming Languages, Past, Present and Future, http://www.computer.org/students/looking/spring97/janlee/ , 1997
C. H. Lindsey, A History of Algol 68, History of Programming Languages II, 1993.