The if keyword is so prevalent in programming that it seems to just be part of it. However, with an integer value and a goto statement, one can easily simulate the functionality of an if.

Which means it's not necessary for a language to have dedicated conditional keywords in order to achieve that functionality. Which in turn makes me think that there must have been a time before somebody created the first if to be used in a language.

So, my question is: What was the first time a language offered a dedicated keyword for conditional execution?

The word itself doesn't really matter here, it could be AS_IT_OCCURS_THAT instead of if for all I care. What does matter is that we have a keyword with the one and only purpose of choosing the code to execute next, based on a boolean condition.

Also, to clear up an ambiguity about "a language offered a dedicated keyword", I'm talking about a working implementation of a language; so that it was an actually usable tool for a programmer.