Superplan

Superplan was a high-level programming language developed between 1949 and 1951 by Heinz Rutishauser, the name being a reference to "Rechenplan" (i.e. computation plan), in Konrad Zuse's terminology designating a single Plankalkül program.
The language was described in Rutishauser's 1951 publication "Über automatische Rechenplanfertigung bei programmgesteuerten Rechenmaschinen" (i.e. "Automatically created Computation Plans for Program-Controlled Computing Machines").
Superplan introduced the keyword "for" resp. the German für with its for loop, which had the following form (formula_1 being an array):
 Für i="base"("increment")"limit": formula_1 + "addend" = formula_1