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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 cansimulate 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.

The Analytical Engine designed in 1837 was capable of conditional branches

From the wiki (emphasis mine):

The programming language to be employed by users was akin to modern
day assembly languages. Loops and conditional branching were possible,
and so the language as conceived would have been Turing-complete as
later defined by Alan Turing.

The wiki later provides an example of the conditional being executed (with the code represented on cards):

For example, a factorial program would be written as:

N0 6 

N1 1 

N2 1 

× 

L1 

L0 

S1

- 

L0 

L2 

S0 

L2 

L0 

CB?11 

where the CB is the conditional branch instruction or "combination card" used to make the control flow jump,
in this case backwards by 11 cards.

Ada Lovelace may very well be the first to have written a program for this machine.

Ada Lovelace's notes were labelled alphabetically from A to G. In note G, she describes an algorithm for the Analytical Engine to compute Bernoulli numbers. It is considered to be the first published algorithm ever specifically tailored for implementation on a computer, and Ada Lovelace has often been cited as the first computer programmer for this reason.

Computers since ENIAC have had conditional branch instructions (like jump if zero), which means assembly languages have had such a statement since the beginning, and there is no logical reason for higher-level languages to ever have forgone using it.

While it's probably theoretically possible to make programs with just your indirect jump idea, you sort of have a chicken and egg problem where it's difficult to get the branch address into the register conditionally in the first place. Implementing a conditional branch using only indirect jumps would add several instructions every time you needed to make a choice, using precious time, memory, and registers,

The answer would, by definition, be the first programming language.

A little bit of free CS101 here...

All algorithms can be expressed using 3 elements: sequence, selection, and iteration. Those are the basic building-blocks of a computer program. In order to express an algorithm with a programming language, it has to support those 3 elements in some form. An "if" check is of course a kind of selection.

Sequence, Selection, and Iteration are the basic elements that we use
to tell the computer what to do. The code will definitely look
different depending on the programming language we use, but the
algorithm will be the same.

So let’s describe these elements:

• Sequence– the order we want the
  computer to execute the instructions we provide as programmers. For
  example, do this first, then do this, then do that, and so forth.


• Selection– selecting which path of an algorithm to execute depending
  on some criteria. For example, if you passed a class in school, then
  we execute the operations that clap and cheer and play a song. But if
  you didn’t pass the class, then maybe we would say, “Better luck next
  time, hang in there!”


• Iteration– looping or repeating. Many times, we
  want to be able to repeat a set of operations a specific number of
  times or until some condition occurs.

To get down deeper into computability theory, we call the ability of a model to express any algorithm Turing completeness, and selection is required for this. Most CS types will tell you than anything that isn't Turing complete isn't really a programming language.

So by definition every programming language has some means of selection, and always has. Without that, you don't really have a programming language.

I'm going to go out on a limb here and assume that what is wanted is not a language that has conditional branches i.e. an equivalent to

if condition then goto someLabel

because Turing complete computers have had that since the beginning. I'm going to assume we are talking about a block structured conditional like

if condition

    some arbitrary sequence of statements including perhaps nested ifs

else 

    some other arbitrary sequence of statements including perhaps nested ifs

Some early contenders for that would be:

• Lisp (1958) which has an if and cond function. I think condpredates if. When I learned Lisp in the 1980's I'm fairly sure that if wasn't there.


• Algol 60 (1960) which has the structured if inherited by most modern imperative languages

Early versions of FORTRAN and COBOL did not have structured if statements as far as I know.