when was the rule for the pawn being allowed to move 2 squares invented?

Do you know when this rule was invented? If so, post below! If you have no clue, say "multiple choice" in the chat, and I will give you a multiple choice!

Actually there is pretty solid evidence that these "new" rules were introduced around 1500.

The earliest preserved chess book is Luis de Lucena's Arte de axedres printed in 1496 or 1497 and published in Spanish. It contains a number of chess puzzles, some using the "old" rules (Pawns only move one step), some using the "new" rules. Each puzzle is labelled as to which rules set it uses.

So the change-over was taking place right around then.

that stands to reason because en passant was first implemented 1615

A History of chess by H.J.R. Murray

https://web.archive.org/web/20140708090911/http://www.chesscafe.com/text/review883.pdf

A world of chess

https://chesscafe.com/book-reviews/a-world-of-chess/

A History of Chess

http://www.thechessmind.net/blog/2012/12/20/book-notice-yuri-averbakhs-a-history-of-chess.html

https://www.newinchess.com/media/wysiwyg/product_pdf/2770.pdf

Doesn't answer the question

Actually there is pretty solid evidence that these "new" rules were introduced around 1500.

The earliest preserved chess book is Luis de Lucena's Arte de axedres printed in 1496 or 1497 and published in Spanish. It contains a number of chess puzzles, some using the "old" rules (Pawns only move one step), some using the "new" rules. Each puzzle is labelled as to which rules set it uses.

So the change-over was taking place right around then.

Doesn't answer the question