I'd say red ottomans gives the most feelings. I have several arguments for this but I will also take in account that most majors also share red colours.

DL;DR
- Ottomans flag is mainly red.
- Red colour gives the human brain a feeling of threat. (works good for expanding countries)

The flag part, I think you will all get. But the threatening part might take some explaining.

It has been tested in several occurrences with different people in several games if colours changes the way a players makes his choices in a game. And almost all of the tests show a positive result. For example, when playing a strategy game, it is advised to pick a blue color since it enhances the left brains logical thinking, and red enhances the chance of aggressive actions by a player.

If you're yourself the colour red, the chances are you will less likely take things in consideration and JUST DO IT [s](sorry)[/s] since you feel like the powerful one. While meeting a red player as another colour would increase your awareness of that player. You WILL feel more threatened than you would normally do, makes it less likely you would take action against.

This is why I would suggest putting Ottoman colours as red, since they're supposed to feel threatening.

@valrossenOliver
You have to be a little more specific though (an RGB code would help), I did try "Turkey Red" but it became very hard to distiguish between that and England/Britain.
Like myself, you might start here, ( https://en.wikipedia.org/wiki/Category:Shades_of_red ), ( https://en.wikipedia.org/wiki/Shades_of_red ) and try to find a shade, (I spent several hours, myself, trying to find one) you think suits the Ottomans but also is easy to distinguish on the map.

https://en.wikipedia.org/wiki/Shades_of_red

England Spanish Red (230, 0, 38)
Ottomans Carmine (150, 0, 24)
Muscovy Scarlet (255, 36, 0)

This way they wouldn't be too similar, and muscovy would fit a little bit more like their orange-ish flag.

There's also TURKEY RED which would fit the ottomans very good.... since it's their real colour. ;P
https://en.wikipedia.org/wiki/Turkey_red

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