"Assembly" is not a programming language...
I think you need to rethink that statement.
The earliest computers were often programmed without the help of a programming language, by writing programs in absolute machine language. The programs, in decimal or binary form, were read in from punched cards or magnetic tape, or toggled in on switches on the front panel of the computer. Absolute machine languages were later termed first-generation programming languages (1GL).
The next step was development of so-called second-generation programming languages (2GL) or assembly languages, which were still closely tied to the instruction set architecture of the specific computer. These served to make the program much more human-readable, and relieved the programmer of tedious and error-prone address calculations.
The first high-level programming languages, or third-generation programming languages (3GL), were written in the 1950s. An early high-level programming language to be designed for a computer was Plankalkül, developed for the German Z3 by Konrad Zuse between 1943 and 1945. However, it was not implemented until 1998 and 2000. - Wikipedia