It’s fun to think about which modern games could have existed in the middle ages or antiquity.
Component complexity is probably the biggest limiting factor. Some components would have been very difficult or impossible to produce. The available printing technologies is a major one. Depending on how far we go back easily shuffleable cards are probably out and cards with lots of text or complex symbology are almost certainly out. So are fancy boards. Simpler boards (chess or go grids, hex) are fine. Meeples, dice, coins, tokens, bags, cups are easy.
Rules complexity might be another factor since it would be more difficult to record and reproduce very complex rules. Some kind of thematic connection woudn’t hurt either. I guess you could try to explain Star Realms as heavenly chariots :)
Abstracts are a category that works well since we have a bunch of examples of those actually existing. Simple dice games, bidding games, certain drafting games should work as well.
Some specific examples of games I like to imagine existing in the past are War Chest, Onitama and Azul. Thematically they would fit well, simple rules, manageable components.
I wonder which of the more complex euros could have worked. Perhaps a simpler version of Castles of Burgundy? Fewer building types to keep component and rules complexity under control. Or maybe something like Ra.
It is curious, but its sometimes like this even with “simple” innovations, it takes a lot of time. Wheels were invented thousands of years ago. So were boxes for transportation. Maybe suitcases are an improvement over a wooden box but only came on the stage a hundred years ago or so. But it took until, what, the 70s for someone to think of putting some small wheels on a suitcase? Imagine travel with these old suitcases back then and how different this is now, with such a tiny addition of things that were already invented.
Many of the modern boardgames probably could exist back then, sure maybe the pieces are bigger, the cardboard is wood or similar but in principle, many of these do not require some high tech technology to reproduce with alternative materials. Rules could be written on papyrus or similar. But most of these things would never survive to the present day, or at the very least, we would be lucky to find it.
Rules complexity might be another factor since it would be more difficult to record and reproduce very complex rules.
Backgammon is about 5000 years old and sets seldomly include a rulebook, they assume someone taught you how to play and, at least for me, it’s such a complex game in terms of mechanics.
